WO2010002331A1 - Apparatus and method for exposing laboratory animals to a test substance - Google Patents

Apparatus and method for exposing laboratory animals to a test substance Download PDF

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Publication number
WO2010002331A1
WO2010002331A1 PCT/SE2009/050732 SE2009050732W WO2010002331A1 WO 2010002331 A1 WO2010002331 A1 WO 2010002331A1 SE 2009050732 W SE2009050732 W SE 2009050732W WO 2010002331 A1 WO2010002331 A1 WO 2010002331A1
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WO
WIPO (PCT)
Prior art keywords
mixing chamber
test substance
common mixing
animal
injector
Prior art date
Application number
PCT/SE2009/050732
Other languages
French (fr)
Inventor
Orest Lastow
Original Assignee
Astrazeneca Ab
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Publication date
Application filed by Astrazeneca Ab filed Critical Astrazeneca Ab
Publication of WO2010002331A1 publication Critical patent/WO2010002331A1/en

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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61DVETERINARY INSTRUMENTS, IMPLEMENTS, TOOLS, OR METHODS
    • A61D7/00Devices or methods for introducing solid, liquid, or gaseous remedies or other materials into or onto the bodies of animals
    • A61D7/04Devices for anaesthetising animals by gases or vapours; Inhaling devices
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; CARE OF BIRDS, FISHES, INSECTS; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K1/00Housing animals; Equipment therefor
    • A01K1/02Pigsties; Dog-kennels; Rabbit-hutches or the like
    • A01K1/03Housing for domestic or laboratory animals
    • A01K1/031Cages for laboratory animals; Cages for measuring metabolism of animals
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; CARE OF BIRDS, FISHES, INSECTS; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K1/00Housing animals; Equipment therefor
    • A01K1/06Devices for fastening animals, e.g. halters, toggles, neck-bars or chain fastenings
    • A01K1/0613Devices for immobilisation or restraint of animals, e.g. chutes

Definitions

  • the present invention relates to techniques for exposing laboratory animals to a test substance, and in particular to an apparatus and method for simultaneous exposure of the test substance for inhalation by several laboratory animals.
  • US4721060 discloses a respiratory exposure system of so-called flow-past design for supplying a gaseous material, containing a test substance of the form of a gas or an aerosol, to the noses of laboratory animals and hence their respiratory system.
  • the exposure system is formed by a concentric arrangement of vertical inner and outer manifolds.
  • the outer manifold connects with a plurality of inhalation chambers for holding an individual animal, and the inner manifold connects with tubes that extend into a respective inhalation chamber.
  • the upper end of the outer manifold and the lower end of the inner manifold are closed.
  • the gaseous material is supplied to the upper end of the inner manifold, flows through the tubes to points adjacent the noses of the animals in the inhalation chambers, and is expelled through the bottom of the outer manifold.
  • This exposure system is alleged to produce a highly uniform dose of the gaseous material to the lungs of the animals. Similar exposure systems are known from US4520808, US4860741, US5109797, US5297502, and US5896829.
  • a first aspect of the invention is an apparatus for exposing laboratory animals to a test substance, said apparatus comprising: a common mixing chamber for holding a breathable gas; an injector for injecting the test substance into the breathable gas in the common mixing chamber; a plurality of animal holders in fluid communication with the common mixing chamber, each animal holder being designed to accommodate a laboratory animal such that the laboratory animal is able to inhale from and exhale into the common mixing chamber; and means for selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber.
  • the inventive apparatus can be operated with a lower or no through- flow of breathable gas while the laboratory animals are exposed to the test substance.
  • the inventive apparatus may be operated with a through-flow of breathable gas that yields an exchange rate of ⁇ 1 during an exposure procedure.
  • the inventive apparatus provides for an improved efficiency, i.e. an increase in the fraction of the test substance that is inhaled during an exposure procedure.
  • the inventive apparatus has the potential of being less stressful for the animals.
  • the reduced exchange rate may also provide for an improved Safety, Health and Environment (SHE), since smaller gas volumes and less test substance leave the mixing chamber during an exposure procedure.
  • SHE Safety, Health and Environment
  • the compounds include at least one of carbon dioxide and water.
  • the selective removing means comprises an extraction material that absorbs, adsorbs or binds said one or more compounds.
  • a simple and robust solution is to arrange the extraction material inside the mixing chamber.
  • Such an extraction material may comprise a desiccant.
  • the common mixing chamber is formed as a cylinder, which provides for a simple construction.
  • the cylinder may have an essentially circular cross- section. Such a cross-section may improve the ability to achieve a desired uniformity in the mixing between the test substance and the breathable gas, and may also facilitate fluid dynamic calculations for optimising the mixing chamber.
  • the injector may be arranged to inject the test substance along the central axis of the cylinder to further provide for a uniform mixing.
  • the exposure apparatus comprises a mixing element which is operable to generate a fluid motion within the mixing chamber, in order to further improve the mixing between test substance and breathable gas and/or to prevent sedimentation of the test substance.
  • the mixing element may comprise an impeller, which may be spaced from the inner walls of the common mixing chamber. Spacing the impeller from the walls has been found to improve the mixing within the chamber.
  • the mixing chamber comprises a detachable bottom plate, wherein the mixing element is joined with a rotatable axis extending through the bottom plate.
  • the mixing chamber is of modular construction, which may allow for simple dismantling and cleaning. This construction also allows the bottom plate to be exchanged, for example if it is desired to operate the exposure apparatus without a mixing element or with a different placement or design of the mixing element.
  • the mixing chamber is at least partly defined by a cylindrical top part and a cylindrical bottom part that a detachably interconnected, wherein the top part comprises a connector for mounting of the injector and a plurality of connectors for mounting of the animal holders.
  • the mixing chamber is thus of modular construction, which may allow for simple dismantling and cleaning. This construction also allows the bottom top part and/or the bottom part to be exchanged, for example it is desired to operate the exposure apparatus with a different arrangement of the animal holders, or with a different placement or design of the injector.
  • the connector for the injector is arranged centrally in a top end wall of the top part, and the connectors for the animal holders are spaced along a peripheral wall portion of the top part.
  • the bottom part comprises an insert that defines an annular chamber for holding the selective removing means, e.g. in the form of the above- mentioned extraction material.
  • This solution provides a well-defined location for the selective removing means, and may ensure that a large surface area of the selective removing means faces the atmosphere in the mixing chamber.
  • the insert and/or the selective removing means may be easily accessed by separating the top and bottom parts for each other. This allows for simple exchange of the insert and/or replenishment, service or exchange of the selective removing means.
  • the insert may have a permeable wall portion that defines at least part of an inner wall of the annular chamber, e.g. in order to ensure adequate contact between the atmosphere inside the mixing chamber and the selective removing means.
  • a second aspect of the invention is a method for exposing laboratory animals to a test substance, said method comprising: operating a gas supply device to provide a breathable gas in a common mixing chamber; operating an injector to inject the test substance into the breathable gas in the common mixing chamber; arranging a plurality of laboratory animals in a respective animal holder, each animal holder being in fluid communication with the common mixing chamber and being designed to accommodate the laboratory animal such that it is able to inhale from and exhale into the common mixing chamber; and selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber.
  • the method of the second aspect shares the advantages of the exposure apparatus of the first aspect, and may comprise further steps corresponding to any of the embodiments and features described above in relation to the first aspect.
  • Fig. 1 is a side view, partly in section, of an exposure apparatus according to a first embodiment of the present invention.
  • Fig. 2 is a perspective view of an exposure apparatus according to a second embodiment of the present invention.
  • Fig. 3 is an exploded view of a modular construction of a tank included in the exposure apparatus of Fig.2.
  • Fig. 4 is a section view of the tank in Fig. 3 when assembled.
  • Fig. 1 illustrates an exposure apparatus according to an embodiment of the present invention.
  • the exposure apparatus comprises a generally cylindrical tank 1 that defines an interior space or mixing chamber 2.
  • the tank 1 is provided with a number of apertures/connectors adapted for connection of different functional modules to the mixing chamber 2.
  • the apertures/connectors may be provided with any suitable means for detachably connecting the respective functional module to the tank.
  • Such means may include fittings, screw threads, bayonet couplings, clamps, snap couplings, friction fits, etc.
  • these modules include a supply 3 of breathable gas, typically ordinary air or dry air, which is in fluid communication with the mixing chamber 2 via an inlet valve 4, and an exhaust system 5 which is in fluid communication with the mixing chamber 2 via an outlet valve 6.
  • Further modules include an injector 7 which is connected to the tank 1 at its top portion and adapted to inject a test substance into the mixing chamber 2, and a plurality of animal holders 8 that are radially connected to the tank 1 along its periphery at a given level below the injector 7.
  • Still further modules include an injection monitoring device 9, which is mounted essentially level with the animal holders to measure one or more characteristics of the injected test substance, and a mixing element 10 which is arranged at the bottom end of the tank 1.
  • laboratory animals such as mice, hamsters, rats, and guinea pigs, among other species, are positioned in the animal holders 8.
  • Each animal holder 8 is open towards the mixing chamber 2, and suitably closed at its outer end. Once positioned in the holder 8, the laboratory animal faces the mixing chamber 2 with its nose-portion, causing the animal to breathe the atmosphere inside the mixing chamber 2.
  • the holders 8, which may be made of metal or plastic, are also referred to as bottles, restrainers, plethysmographic tubes or cages, and are generally known to those skilled in the art.
  • the inlet valve 4 is opened to admit the breathable gas into the mixing chamber 2.
  • the injector 7 is operated to inject the test substance into the breathable gas in the mixing chamber 2, either continuously or as one or more discrete injections, in order to achieve a desired concentration of test substance in the mixing chamber 2 as a function of time.
  • the exposure procedure typically lasts for 1-60 minutes.
  • the mixing element 10 is continuously or intermittently rotated to generate a fluid motion in the mixing chamber 2, e.g. in order to improve the mixing of the test substance with the breathable air and/or to levitate particles of the test substance in the breathable air so as to prevent or at least minimize sedimentation thereof.
  • the mixing element 10 is an impeller which is driven to rotate inside the chamber via a shaft 11 connected to an electrical motor 12 underneath the tank 1.
  • the atmosphere in the mixing chamber 2 is purged, e.g. by opening the valves 4, 6 and setting up a high flow of breathable gas, or another suitable gas, from the supply through the mixing chamber 2 to the exhaust system 5.
  • the exposure apparatus is operated with a low exchange rate of the breathable gas inside the mixing chamber 2, i.a. to economize with the test substance.
  • the exchange rate is governed by the flow rate of breathable gas through the mixing chamber 2.
  • the gas exchange rate is less than one during the exposure procedure, i.e. the breathable gas inside the mixing chamber is at most exchanged once. With such a low exchange rate, since the laboratory animals exhale into the mixing chamber 2, the relative humidity and the concentration of carbon dioxide may increase during the exposure procedure.
  • Carbon dioxide in concentrations above 1-2% may be harmful, or at least unpleasant or stressful, to the animals An accumulation of carbon dioxide may thus affect the breathing ability of the animals.
  • the accumulation of humidity inside the mixing chamber 2 may likewise be undesired since it may affect the laboratory animals, and may require special procedures for cleaning the mixing chamber 2 between exposure procedures. Therefore, as indicated in Fig.l, a material 13 is provided in the tank 1 to extract carbon dioxide and/or water from the atmosphere inside the mixing chamber 2.
  • the extraction material 13 may or may not be a mixture of specialized substances for extracting water and carbon dioxide, respectively.
  • the extraction material may e.g. include soda lime or calcium hydroxide, e.g. in the form of granules, for extraction of carbon dioxide.
  • the extraction material can include any known desiccant, including suitable molecular sieves, silica gel, calcium sulfate, calcium chloride, and montmorillonite clay.
  • the extraction material is desiccant capable of extracting both carbon dioxide and water, e.g. a molecular sieve of a suitable mesh type, e.g. 13X.
  • the skilled person can readily find further extraction materials with desired extraction characteristics, as well as other suitable properties, e.g. with respect to toxicity, handling, shelf life, cost, etc
  • the pressure inside the mixing chamber 2 is suitably maintained essentially constant, typically at atmospheric pressure. This may be achieved by manipulating/controlling the outlet valve 6 and/or the exhaust system 5. Alternatively, the outlet valve 5 may a relief valve set at the desired pressure.
  • the inlet valve 4 and/or the supply 3 may be manipulated/controlled to set up a desired flow of breathable gas through the mixing chamber 2. It is conceivable to operate the exposure apparatus without any admission of breathable gas during the exposure procedure, provided that the carbon dioxide and/or water can be maintained within acceptable limits during the exposure procedure.
  • the breathable gas may be driven into/through the tank 1 by means of an overpressure on the inlet side and/or an under-pressure on the outlet side.
  • the supply 3 could be implemented by a gas container/bottle, or a system for generating pressurized air.
  • the breathable air could be taken directly from the atmosphere surrounding the tank 1. If the test substance is non-hazardous or otherwise environmentally safe, the exhaust system 5 may be excluded and the tank 1 be vented directly to the surrounding atmosphere.
  • Each of the valves 4, 6 may be an on/off valve or a flow-control valve. It is also conceivable to exclude one or both of the valves 4, 6.
  • test substance may be any type of pharmaceutical agent, cosmetic compound or environmental chemical that is to be subjected to respiratory testing using laboratory animals.
  • the test substance may be supplied to the laboratory animals in gaseous form or as an aerosol, i.e. as liquid or solid particles dispersed in the breathing gas.
  • injector 7 Any suitable type of injector 7 may be used, such as a nebulizer or aerosol generator, a metered dose inhaler (MDI), an aerosol dispenser, a pressurized container, a gas injector, etc.
  • MDI metered dose inhaler
  • aerosol dispenser a pressurized container
  • gas injector etc.
  • the test substance is provided as a solution, a micronized suspension or a nanosuspension to a nebulizer which generates a suitable aerosol inside the mixing chamber.
  • an injector that operates essentially without propellant, i.e. an injector that does not use any additional gas to create the aerosol, since this will serve to maintain a low gas exchange rate in the mixing chamber during the exposure procedure. Tests have been successfully performed with such an injector: a nebulizer marketed by PARI Pharma GmbH under the name eFlow ® rapid.
  • a controller 14 may be provided to control the operation of the injector 7 based on the output signal of the injection-monitoring device 8.
  • the monitoring device 9 may e.g. be arranged to measure the concentration the injected test substance. If the injector 7 generates an aerosol, the monitoring device 9 may indicate the quality and/or concentration of the aerosol, and the controller 14 may include a feedback control loop for operating the injector 7 to achieve a set value for the quality/concentration.
  • the monitoring device 9 may use remote sensing, e.g. based on optical properties of the atmosphere inside the mixing chamber, or intrusive sensing, e.g. by using a probe to extract a sample of the atmosphere for analysis.
  • a data logging system could be connected to the monitoring device 9, as well as to additional sensors (not shown) that measure one or more relevant parameters during the exposure procedure.
  • Such parameters may represent the conditions in the mixing chamber 2, such as pressure, temperature, gas composition (CO 2 , O 2 , etc) , relative humidity (RH), etc, or the physiological conditions of the laboratory animals, such as their breathing pattern.
  • the data logging system may store a time record of the measured parameters for later reference.
  • the exposure apparatus may be operated manually, or it may be connected to an automatic control system which operates the valves 4, 6, the supply 3, the exhaust system 5, the injector 7, etc according to a preprogrammed sequence, and optionally based on output signal(s) from the measurement device 9 and/or one or more of the additional sensors.
  • the exposure apparatus of Fig. 1 is modular in as much as the functional modules are detachable from the tank 1. This facilitates replacement and repair of individual functional modules, and enables tailoring of the exposure apparatus for a specific set-up.
  • Figs 2-4 illustrate an exemplifying embodiment in which the tank 1 is also of modular construction, to facilitate dismantling and cleaning of the tank 1.
  • the tank 1 is formed by three interconnected parts: a top cylinder 20, a bottom cylinder 21 and a bottom plate 22.
  • the top cylinder 20 is formed as a tubular shell 20a which is open at the bottom end and closed by a wall portion 20b at the top end.
  • the bottom end has a circumferential flange portion 23 that forms a projecting shoulder 23a and a guide flange 23b.
  • a band of mounting holes 24 for animal holders 8 are provided around the periphery of the tubular shell 20a.
  • the top end wall portion 20b is provided with mounting holes 26 for the above-mentioned additional sensors, as well as a central mounting hole 27 for the injector 7. It is to be understood that any mounting holes 24, 25, 26 that are not used in a specific set-up are suitably sealed, e.g. by attaching a plug member to each such mounting hole.
  • the bottom cylinder 21 is formed as a tubular shell 21a which is open at the top end and closed by an end wall 21b at the other end. As shown in the section view of Fig. 4, the end wall 21b is arranged with a slight axial displacement inwardly from the outer end portion of the shell 21a. A central hole 28 is formed in the end wall 21a so as to receive the rotatable axis 11 with a clearance.
  • the rotatable axis 11 is connected to the electrical motor 12 and has a distal end portion adapted for detachable mounting of the impeller 10.
  • the bottom plate 22 has a central through hole 29 which is formed to sealingly accommodate the rotatable axis 11.
  • the bottom plate 22 also comprises an inlet opening 30 for connection to the supply of breathable gas (3 in Fig. 1) and an outlet opening 31 for connection to the exhaust system (5 in Fig. 6).
  • the bottom plate 22 is shaped to receive a sealing gasket 32 while mating with the outer end portion of the bottom cylinder 21. Any suitable fixing means (not shown) may be used to detachably join the bottom plate 22 to the bottom cylinder 21.
  • a disk-shaped compartment 33 is formed between the plate 22 and the end wall 21b.
  • gas is led into and out of the mixing chamber 2 through the disk- shaped compartment 33 and the clearance around the axis 11.
  • the supply and/or exhaust system is connected to a respective one of the mounting holes 26 in the top surface 20b.
  • the bottom plate 22 further comprises screw holes 34 for attaching a set of legs 35, as well as screw holes (not shown) for attaching a suspending structure (not shown) for the electrical motor 12.
  • a cylindrical cage structure 36 is inserted into the bottom cylinder 21 to peripherally define an annular space 37 for holding aforesaid extraction material (13 in Fig. 1) for extraction of carbon dioxide and/or water.
  • the cage structure 36 comprises a gas permeable wall portion 38, e.g.
  • the top cylinder 20 is mounted onto the bottom cylinder 21, by the flange portion 23 mating with the top end of the bottom cylinder 21, a gasket 39 being arranged on the inner side of the shoulder 23a so as to seal the joint between the cylinders 20, 21.
  • Any suitable fixing means (not shown) may be used to detachably join the cylinders 20, 21.
  • a supporting wheel structure 40 is fitted over the top cylinder 20 into abutment on the shoulder 23a.
  • the wheel structure 40 is designed to support the animal holders 8 when mounted in the holes 24, as shown in Fig. 2.
  • the cylinders 20, 21, the bottom plate 22, the impeller 10, the shaft 11 and the cage 36 may be constructed of any material which is chemically inert to the test substance and can be sanitized, e.g. by heating in an autoclave or by machine washing. Such materials include stainless steel or chlorinated polyvinyl chloride.
  • the exposure apparatus of Figs 2-4 has been tested with a mixing chamber volume of 10 litres, with 10 laboratory rats placed in 10 animal holders, and using the eFlow ® rapid nebulizer for injecting a formulated test substance. The test indicated that the exposure apparatus could be operated with a little as 80 mg formulated test substance and was able to deliver a lung dose of up to 1 mg/kg within a maximum exposure time of 10 minutes.
  • the inventive exposure apparatus yields at least a six-fold improvement in efficiency, i.e. in the inhaled fraction of the test substance that is consumed during an exposure procedure.
  • the invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope and spirit of the invention, which is defined and limited only by the appended patent claims.
  • the tank may have more than one peripheral band of mounting holes for animal holders, or the mounting holes could be arranged in other patterns on the peripheral wall of the tank.
  • the modular tank could be differently configured.
  • the bottom plate could be integrated with the bottom cylinder.
  • the cage structure could be an integral part of the bottom cylinder.
  • test substance and breathable gas may be achieved without the use of a mixing element in the chamber.
  • carbon dioxide/water can be extracted by other means.
  • the atmosphere inside the mixing chamber could be circulated through an external air treatment device. Such air treatment devices are readily available and e.g. used in submarines or spacecrafts.
  • the atmosphere inside the mixing chamber could be circulated through an external tank holding any one of the above- mentioned extraction materials.

Abstract

An apparatus is designed for exposing laboratory animals to a test substance. The apparatus includes a tank defining a common mixing chamber (2). Animal holders (8) are connected to the tank to be in fluid communication with the mixing chamber (2). Each animal holder (8) is designed to accommodate a laboratory animal such that the laboratory animal is able to inhale from and exhale into the mixing chamber (2). The apparatus further includes an injector (7) which is arranged to inject the test substance into the mixing chamber (2), and means (13) for selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the mixing chamber (2). In operation, a breathable gas is admitted into the mixing chamber (2), and the injector (7) is operated to inject the test substance into the breathable gas in the mixing chamber (2), whereby the laboratory animals are simultaneously exposed to the test substance for inhalation. The provision of the selective removal means (13) allow for an acceptable atmosphere to be sustained within the mixing chamber, even with no or low gas exchange rate during the exposure procedure.

Description

Apparatus and method for exposing laboratory animals to a test substance
Technical Field The present invention relates to techniques for exposing laboratory animals to a test substance, and in particular to an apparatus and method for simultaneous exposure of the test substance for inhalation by several laboratory animals.
Background art US4721060 discloses a respiratory exposure system of so-called flow-past design for supplying a gaseous material, containing a test substance of the form of a gas or an aerosol, to the noses of laboratory animals and hence their respiratory system. The exposure system is formed by a concentric arrangement of vertical inner and outer manifolds. The outer manifold connects with a plurality of inhalation chambers for holding an individual animal, and the inner manifold connects with tubes that extend into a respective inhalation chamber. The upper end of the outer manifold and the lower end of the inner manifold are closed. In operation, the gaseous material is supplied to the upper end of the inner manifold, flows through the tubes to points adjacent the noses of the animals in the inhalation chambers, and is expelled through the bottom of the outer manifold. This exposure system is alleged to produce a highly uniform dose of the gaseous material to the lungs of the animals. Similar exposure systems are known from US4520808, US4860741, US5109797, US5297502, and US5896829.
All of these known exposure systems require a continuous and significant flow of gaseous material to be set up through the manifold(s), driven by an over-pressure at a manifold inlet and/or an under-pressure at a manifold outlet. The significant flow causes the majority of the test substance to be blown past the animals without being inhaled, resulting in an inefficient use of the test substance. Typically, less than 1% of the test substance reaches the respiratory system of the animals. Thus, these exposure systems are unsuitable for use with test substances that are expensive or only available in limited quantities. Furthermore, the steady and strong flow of gaseous material may be uncomfortable and stressful to the laboratory animals, which might tend to avoid inhalation of the test substance. Such avoidance response may be undesirable for the sake of uniformity of experiments.
Summary of the Invention
It is an object of the invention to at least partly overcome one or more limitations of the prior art. This and other objects, which will appear from the description below, are at least partly achieved by means of an apparatus and a method according to the independent claims, embodiments thereof being defined by the dependent claims.
A first aspect of the invention is an apparatus for exposing laboratory animals to a test substance, said apparatus comprising: a common mixing chamber for holding a breathable gas; an injector for injecting the test substance into the breathable gas in the common mixing chamber; a plurality of animal holders in fluid communication with the common mixing chamber, each animal holder being designed to accommodate a laboratory animal such that the laboratory animal is able to inhale from and exhale into the common mixing chamber; and means for selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber.
The selective removal of at least part of one or more compounds generated by the exhalation of the laboratory animals makes it possible maintain an acceptable atmosphere inside the mixing chamber even with a low exchange rate of the breathable gas.
Compared to the flow-past systems of the prior art, which operate with a constant and significant through- flow of gaseous material to expel all compounds generated by the exhalation of the laboratory animals, the inventive apparatus can be operated with a lower or no through- flow of breathable gas while the laboratory animals are exposed to the test substance. Typically, the inventive apparatus may be operated with a through-flow of breathable gas that yields an exchange rate of ≤ 1 during an exposure procedure. Thereby, the inventive apparatus provides for an improved efficiency, i.e. an increase in the fraction of the test substance that is inhaled during an exposure procedure.
Furthermore, by allowing for a reduced through- flow of breathable gas, the inventive apparatus has the potential of being less stressful for the animals.
The reduced exchange rate may also provide for an improved Safety, Health and Environment (SHE), since smaller gas volumes and less test substance leave the mixing chamber during an exposure procedure.
In one embodiment, the compounds include at least one of carbon dioxide and water.
In one embodiment, the selective removing means comprises an extraction material that absorbs, adsorbs or binds said one or more compounds. A simple and robust solution is to arrange the extraction material inside the mixing chamber. Such an extraction material may comprise a desiccant. In one embodiment, the common mixing chamber is formed as a cylinder, which provides for a simple construction. The cylinder may have an essentially circular cross- section. Such a cross-section may improve the ability to achieve a desired uniformity in the mixing between the test substance and the breathable gas, and may also facilitate fluid dynamic calculations for optimising the mixing chamber. The injector may be arranged to inject the test substance along the central axis of the cylinder to further provide for a uniform mixing. In one embodiment, the exposure apparatus comprises a mixing element which is operable to generate a fluid motion within the mixing chamber, in order to further improve the mixing between test substance and breathable gas and/or to prevent sedimentation of the test substance. The mixing element may comprise an impeller, which may be spaced from the inner walls of the common mixing chamber. Spacing the impeller from the walls has been found to improve the mixing within the chamber.
In one embodiment, the mixing chamber comprises a detachable bottom plate, wherein the mixing element is joined with a rotatable axis extending through the bottom plate. Thus, the mixing chamber is of modular construction, which may allow for simple dismantling and cleaning. This construction also allows the bottom plate to be exchanged, for example if it is desired to operate the exposure apparatus without a mixing element or with a different placement or design of the mixing element.
In one embodiment, the mixing chamber is at least partly defined by a cylindrical top part and a cylindrical bottom part that a detachably interconnected, wherein the top part comprises a connector for mounting of the injector and a plurality of connectors for mounting of the animal holders. The mixing chamber is thus of modular construction, which may allow for simple dismantling and cleaning. This construction also allows the bottom top part and/or the bottom part to be exchanged, for example it is desired to operate the exposure apparatus with a different arrangement of the animal holders, or with a different placement or design of the injector. In one embodiment, the connector for the injector is arranged centrally in a top end wall of the top part, and the connectors for the animal holders are spaced along a peripheral wall portion of the top part.
In one embodiment, the bottom part comprises an insert that defines an annular chamber for holding the selective removing means, e.g. in the form of the above- mentioned extraction material. This solution provides a well-defined location for the selective removing means, and may ensure that a large surface area of the selective removing means faces the atmosphere in the mixing chamber. Furthermore, the insert and/or the selective removing means may be easily accessed by separating the top and bottom parts for each other. This allows for simple exchange of the insert and/or replenishment, service or exchange of the selective removing means. The insert may have a permeable wall portion that defines at least part of an inner wall of the annular chamber, e.g. in order to ensure adequate contact between the atmosphere inside the mixing chamber and the selective removing means.
A second aspect of the invention is a method for exposing laboratory animals to a test substance, said method comprising: operating a gas supply device to provide a breathable gas in a common mixing chamber; operating an injector to inject the test substance into the breathable gas in the common mixing chamber; arranging a plurality of laboratory animals in a respective animal holder, each animal holder being in fluid communication with the common mixing chamber and being designed to accommodate the laboratory animal such that it is able to inhale from and exhale into the common mixing chamber; and selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber. The method of the second aspect shares the advantages of the exposure apparatus of the first aspect, and may comprise further steps corresponding to any of the embodiments and features described above in relation to the first aspect.
Still other objectives, features, aspects and advantages of the present invention will appear from the following detailed description, from the attached claims as well as from the drawings.
Brief Description of the Drawings
Embodiments of the invention will now be described in more detail with reference to the accompanying schematic drawings, in which the same reference numerals are used to identify corresponding elements.
Fig. 1 is a side view, partly in section, of an exposure apparatus according to a first embodiment of the present invention.
Fig. 2 is a perspective view of an exposure apparatus according to a second embodiment of the present invention
Fig. 3 is an exploded view of a modular construction of a tank included in the exposure apparatus of Fig.2. Fig. 4 is a section view of the tank in Fig. 3 when assembled.
Detailed Description of Exemplary Embodiments
Fig. 1 illustrates an exposure apparatus according to an embodiment of the present invention. The exposure apparatus comprises a generally cylindrical tank 1 that defines an interior space or mixing chamber 2. The tank 1 is provided with a number of apertures/connectors adapted for connection of different functional modules to the mixing chamber 2. In this and other embodiments described herein, the apertures/connectors may be provided with any suitable means for detachably connecting the respective functional module to the tank. Such means may include fittings, screw threads, bayonet couplings, clamps, snap couplings, friction fits, etc. In the illustrated example, these modules include a supply 3 of breathable gas, typically ordinary air or dry air, which is in fluid communication with the mixing chamber 2 via an inlet valve 4, and an exhaust system 5 which is in fluid communication with the mixing chamber 2 via an outlet valve 6. Further modules include an injector 7 which is connected to the tank 1 at its top portion and adapted to inject a test substance into the mixing chamber 2, and a plurality of animal holders 8 that are radially connected to the tank 1 along its periphery at a given level below the injector 7. Still further modules include an injection monitoring device 9, which is mounted essentially level with the animal holders to measure one or more characteristics of the injected test substance, and a mixing element 10 which is arranged at the bottom end of the tank 1. In operation, laboratory animals such as mice, hamsters, rats, and guinea pigs, among other species, are positioned in the animal holders 8. Each animal holder 8 is open towards the mixing chamber 2, and suitably closed at its outer end. Once positioned in the holder 8, the laboratory animal faces the mixing chamber 2 with its nose-portion, causing the animal to breathe the atmosphere inside the mixing chamber 2. The holders 8, which may be made of metal or plastic, are also referred to as bottles, restrainers, plethysmographic tubes or cages, and are generally known to those skilled in the art. In one exemplary exposure procedure, the inlet valve 4 is opened to admit the breathable gas into the mixing chamber 2. Then, the injector 7 is operated to inject the test substance into the breathable gas in the mixing chamber 2, either continuously or as one or more discrete injections, in order to achieve a desired concentration of test substance in the mixing chamber 2 as a function of time. The exposure procedure typically lasts for 1-60 minutes. During the exposure, the mixing element 10 is continuously or intermittently rotated to generate a fluid motion in the mixing chamber 2, e.g. in order to improve the mixing of the test substance with the breathable air and/or to levitate particles of the test substance in the breathable air so as to prevent or at least minimize sedimentation thereof. In the illustrated example, the mixing element 10 is an impeller which is driven to rotate inside the chamber via a shaft 11 connected to an electrical motor 12 underneath the tank 1. After the exposure procedure, the atmosphere in the mixing chamber 2 is purged, e.g. by opening the valves 4, 6 and setting up a high flow of breathable gas, or another suitable gas, from the supply through the mixing chamber 2 to the exhaust system 5. During the exposure procedure, the exposure apparatus is operated with a low exchange rate of the breathable gas inside the mixing chamber 2, i.a. to economize with the test substance. The exchange rate is governed by the flow rate of breathable gas through the mixing chamber 2. Typically, the gas exchange rate is less than one during the exposure procedure, i.e. the breathable gas inside the mixing chamber is at most exchanged once. With such a low exchange rate, since the laboratory animals exhale into the mixing chamber 2, the relative humidity and the concentration of carbon dioxide may increase during the exposure procedure. Carbon dioxide in concentrations above 1-2% may be harmful, or at least unpleasant or stressful, to the animals An accumulation of carbon dioxide may thus affect the breathing ability of the animals. The accumulation of humidity inside the mixing chamber 2 may likewise be undesired since it may affect the laboratory animals, and may require special procedures for cleaning the mixing chamber 2 between exposure procedures. Therefore, as indicated in Fig.l, a material 13 is provided in the tank 1 to extract carbon dioxide and/or water from the atmosphere inside the mixing chamber 2. The extraction material 13 may or may not be a mixture of specialized substances for extracting water and carbon dioxide, respectively. The extraction material may e.g. include soda lime or calcium hydroxide, e.g. in the form of granules, for extraction of carbon dioxide. One such carbon dioxide absorbent is Amsorb® Plus marketed by Armstrong Medical. Other possible extraction materials for extraction of carbon dioxide include lithium hydroxide, solid amine sorbents, specialized molecular sieves, and magnesium compounds such as magnesium oxide, magnesium hydroxide or magnesium hydroxy carbonate. For extraction of water, the extraction material can include any known desiccant, including suitable molecular sieves, silica gel, calcium sulfate, calcium chloride, and montmorillonite clay. In a specific embodiment, the extraction material is desiccant capable of extracting both carbon dioxide and water, e.g. a molecular sieve of a suitable mesh type, e.g. 13X. The skilled person can readily find further extraction materials with desired extraction characteristics, as well as other suitable properties, e.g. with respect to toxicity, handling, shelf life, cost, etc
During the exposure procedure, the pressure inside the mixing chamber 2 is suitably maintained essentially constant, typically at atmospheric pressure. This may be achieved by manipulating/controlling the outlet valve 6 and/or the exhaust system 5. Alternatively, the outlet valve 5 may a relief valve set at the desired pressure. During the exposure procedure, the inlet valve 4 and/or the supply 3 may be manipulated/controlled to set up a desired flow of breathable gas through the mixing chamber 2. It is conceivable to operate the exposure apparatus without any admission of breathable gas during the exposure procedure, provided that the carbon dioxide and/or water can be maintained within acceptable limits during the exposure procedure. The breathable gas may be driven into/through the tank 1 by means of an overpressure on the inlet side and/or an under-pressure on the outlet side. For example, the supply 3 could be implemented by a gas container/bottle, or a system for generating pressurized air. Alternatively, the breathable air could be taken directly from the atmosphere surrounding the tank 1. If the test substance is non-hazardous or otherwise environmentally safe, the exhaust system 5 may be excluded and the tank 1 be vented directly to the surrounding atmosphere. Each of the valves 4, 6 may be an on/off valve or a flow-control valve. It is also conceivable to exclude one or both of the valves 4, 6.
The test substance may be any type of pharmaceutical agent, cosmetic compound or environmental chemical that is to be subjected to respiratory testing using laboratory animals. The test substance may be supplied to the laboratory animals in gaseous form or as an aerosol, i.e. as liquid or solid particles dispersed in the breathing gas.
Any suitable type of injector 7 may be used, such as a nebulizer or aerosol generator, a metered dose inhaler (MDI), an aerosol dispenser, a pressurized container, a gas injector, etc.
In one specific embodiment, the test substance is provided as a solution, a micronized suspension or a nanosuspension to a nebulizer which generates a suitable aerosol inside the mixing chamber.
It may be preferable to select an injector that operates essentially without propellant, i.e. an injector that does not use any additional gas to create the aerosol, since this will serve to maintain a low gas exchange rate in the mixing chamber during the exposure procedure. Tests have been successfully performed with such an injector: a nebulizer marketed by PARI Pharma GmbH under the name eFlow ®rapid.
As shown in Fig. 1, a controller 14 may be provided to control the operation of the injector 7 based on the output signal of the injection-monitoring device 8. The monitoring device 9 may e.g. be arranged to measure the concentration the injected test substance. If the injector 7 generates an aerosol, the monitoring device 9 may indicate the quality and/or concentration of the aerosol, and the controller 14 may include a feedback control loop for operating the injector 7 to achieve a set value for the quality/concentration. The monitoring device 9 may use remote sensing, e.g. based on optical properties of the atmosphere inside the mixing chamber, or intrusive sensing, e.g. by using a probe to extract a sample of the atmosphere for analysis.
Although not shown in Fig. 1, it is to be understood that a data logging system could be connected to the monitoring device 9, as well as to additional sensors (not shown) that measure one or more relevant parameters during the exposure procedure.
Such parameters may represent the conditions in the mixing chamber 2, such as pressure, temperature, gas composition (CO2, O2, etc) , relative humidity (RH), etc, or the physiological conditions of the laboratory animals, such as their breathing pattern. The data logging system may store a time record of the measured parameters for later reference.
Likewise, it is to be understood that the exposure apparatus may be operated manually, or it may be connected to an automatic control system which operates the valves 4, 6, the supply 3, the exhaust system 5, the injector 7, etc according to a preprogrammed sequence, and optionally based on output signal(s) from the measurement device 9 and/or one or more of the additional sensors.
The exposure apparatus of Fig. 1 is modular in as much as the functional modules are detachable from the tank 1. This facilitates replacement and repair of individual functional modules, and enables tailoring of the exposure apparatus for a specific set-up.
Figs 2-4 illustrate an exemplifying embodiment in which the tank 1 is also of modular construction, to facilitate dismantling and cleaning of the tank 1. In the illustrated example, the tank 1 is formed by three interconnected parts: a top cylinder 20, a bottom cylinder 21 and a bottom plate 22.
The top cylinder 20 is formed as a tubular shell 20a which is open at the bottom end and closed by a wall portion 20b at the top end. The bottom end has a circumferential flange portion 23 that forms a projecting shoulder 23a and a guide flange 23b. A band of mounting holes 24 for animal holders 8 (only shown in Fig. 2) are provided around the periphery of the tubular shell 20a. Within the band of mounting holes 24, there is also provided a mounting hole 25 for the monitoring device 9. The top end wall portion 20b is provided with mounting holes 26 for the above-mentioned additional sensors, as well as a central mounting hole 27 for the injector 7. It is to be understood that any mounting holes 24, 25, 26 that are not used in a specific set-up are suitably sealed, e.g. by attaching a plug member to each such mounting hole.
The bottom cylinder 21 is formed as a tubular shell 21a which is open at the top end and closed by an end wall 21b at the other end. As shown in the section view of Fig. 4, the end wall 21b is arranged with a slight axial displacement inwardly from the outer end portion of the shell 21a. A central hole 28 is formed in the end wall 21a so as to receive the rotatable axis 11 with a clearance. The rotatable axis 11 is connected to the electrical motor 12 and has a distal end portion adapted for detachable mounting of the impeller 10.
The bottom plate 22 has a central through hole 29 which is formed to sealingly accommodate the rotatable axis 11. The bottom plate 22 also comprises an inlet opening 30 for connection to the supply of breathable gas (3 in Fig. 1) and an outlet opening 31 for connection to the exhaust system (5 in Fig. 6). The bottom plate 22 is shaped to receive a sealing gasket 32 while mating with the outer end portion of the bottom cylinder 21. Any suitable fixing means (not shown) may be used to detachably join the bottom plate 22 to the bottom cylinder 21. When the bottom plate 22 mates with the bottom cylinder 21, as shown in Fig. 4, a disk-shaped compartment 33 is formed between the plate 22 and the end wall 21b. Thus, in the illustrated embodiment, gas is led into and out of the mixing chamber 2 through the disk- shaped compartment 33 and the clearance around the axis 11. In an alternative configuration, the supply and/or exhaust system is connected to a respective one of the mounting holes 26 in the top surface 20b. The bottom plate 22 further comprises screw holes 34 for attaching a set of legs 35, as well as screw holes (not shown) for attaching a suspending structure (not shown) for the electrical motor 12. A cylindrical cage structure 36 is inserted into the bottom cylinder 21 to peripherally define an annular space 37 for holding aforesaid extraction material (13 in Fig. 1) for extraction of carbon dioxide and/or water. The cage structure 36 comprises a gas permeable wall portion 38, e.g. formed by a wire grid or a perforated metal sheet. The top cylinder 20 is mounted onto the bottom cylinder 21, by the flange portion 23 mating with the top end of the bottom cylinder 21, a gasket 39 being arranged on the inner side of the shoulder 23a so as to seal the joint between the cylinders 20, 21. Any suitable fixing means (not shown) may be used to detachably join the cylinders 20, 21.
A supporting wheel structure 40 is fitted over the top cylinder 20 into abutment on the shoulder 23a. The wheel structure 40 is designed to support the animal holders 8 when mounted in the holes 24, as shown in Fig. 2.
The cylinders 20, 21, the bottom plate 22, the impeller 10, the shaft 11 and the cage 36 may be constructed of any material which is chemically inert to the test substance and can be sanitized, e.g. by heating in an autoclave or by machine washing. Such materials include stainless steel or chlorinated polyvinyl chloride. The exposure apparatus of Figs 2-4 has been tested with a mixing chamber volume of 10 litres, with 10 laboratory rats placed in 10 animal holders, and using the eFlow ®rapid nebulizer for injecting a formulated test substance. The test indicated that the exposure apparatus could be operated with a little as 80 mg formulated test substance and was able to deliver a lung dose of up to 1 mg/kg within a maximum exposure time of 10 minutes. Compared to a commercially available Battelle flow-past exposure system, of the type discussed by way of introduction with reference to US 4721060, the inventive exposure apparatus yields at least a six-fold improvement in efficiency, i.e. in the inhaled fraction of the test substance that is consumed during an exposure procedure. The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope and spirit of the invention, which is defined and limited only by the appended patent claims. For example, the tank may have more than one peripheral band of mounting holes for animal holders, or the mounting holes could be arranged in other patterns on the peripheral wall of the tank.
Furthermore, the modular tank could be differently configured. For example, the bottom plate could be integrated with the bottom cylinder. Similarly, the cage structure could be an integral part of the bottom cylinder.
Still further, it should be understood that an appropriate mixing between test substance and breathable gas may be achieved without the use of a mixing element in the chamber. It is also to be understood that carbon dioxide/water can be extracted by other means. For example, the atmosphere inside the mixing chamber could be circulated through an external air treatment device. Such air treatment devices are readily available and e.g. used in submarines or spacecrafts. Similarly, the atmosphere inside the mixing chamber could be circulated through an external tank holding any one of the above- mentioned extraction materials.

Claims

I . An apparatus for exposing laboratory animals to a test substance, said apparatus comprising: a common mixing chamber (2) for holding a breathable gas; an injector (7) for injecting the test substance into the breathable gas in the common mixing chamber (2); a plurality of animal holders (8) in fluid communication with the common mixing chamber (2), each animal holder (8) being designed to accommodate a laboratory animal such that the laboratory animal is able to inhale from and exhale into the common mixing chamber (2); and means (13) for selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber
(2).
2. The apparatus of claim 1, wherein said compounds include at least one of carbon dioxide and water.
3. The apparatus of claim 1 or 2, wherein said selective removing means comprises an extraction material (13) that absorbs, adsorbs or binds said one or more compounds.
4. The apparatus of claim 3, wherein the extraction material (13) is arranged inside the common mixing chamber (2).
5. The apparatus of claim 3 or 4, wherein the extraction material (13) comprises a desiccant.
6. The apparatus of any preceding claim, wherein the common mixing chamber (2) is formed as a cylinder.
7. The apparatus of claim 6, wherein the cylinder has an essentially circular cross- section.
8. The apparatus of claim 6 or 7, wherein the injector (7) is arranged to inject the test substance along the central axis of the cylinder.
9. The apparatus of any preceding claim, further comprising a mixing element (10) operable to generate a fluid motion within the common mixing chamber (2).
10. The apparatus of claim 9, wherein the mixing element comprises an impeller (10).
I I. The apparatus of claim 10, wherein the impeller (10) is spaced from the inner walls of the common mixing chamber (2).
12. The apparatus of any one of claims 9-11, wherein the common mixing chamber
(2) comprises a detachable bottom plate (22), wherein the mixing element (10) is joined with a rotatable axis (11) extending through the bottom plate (22).
13. The apparatus of any preceding claim, wherein the common mixing chamber (2) is at least partly defined by a cylindrical top part (20) and a cylindrical bottom part (21) that a detachably interconnected, wherein the top part (20) comprises a connector (27) for mounting of the injector (7) and a plurality of connectors (24) for mounting of the animal holders (8).
14. The apparatus of claim 13, wherein the connector (27) for the injector (7) is arranged centrally in a top end wall (20b) of the top part (20), and wherein the connectors (24) for the animal holders (8) are spaced along a peripheral wall portion (20a) of the top part (20).
15. The apparatus of claim 13 or 14, wherein the bottom part (21) comprises an insert (36) that defines an annular chamber (37) for holding said selective removing means (13).
16. The apparatus of claim 15, wherein the insert (36) has a permeable wall portion (38) that defines at least part of an inner wall of the annular chamber (37).
17. The apparatus of any preceding claim, further comprising an actuator (4, 6) for setting the flow of breathable gas through the common mixing chamber (2) such that the exchange rate of breathable gas is ≤ 1 during said exposing.
18. The apparatus of any preceding claim, wherein there is essentially no flow of breathable gas through the common mixing chamber (2) during said exposing.
19. The apparatus of any preceding claim, wherein the injector (7) is configured to inject the test substance without propellant.
20. A method for exposing laboratory animals to a test substance, said method comprising: operating a gas supply device (3, 4) to provide a breathable gas in a common mixing chamber (2); operating an injector (7) to inject the test substance into the breathable gas in the common mixing chamber (2); arranging a plurality of laboratory animals in a respective animal holder (8), each animal holder (8) being in fluid communication with the common mixing chamber (2) and being designed to accommodate the laboratory animal such that it is able to inhale from and exhale into the common mixing chamber (2); and selectively removing at least part of one or more compounds generated by the exhalation of the laboratory animals into the common mixing chamber (2).
PCT/SE2009/050732 2008-07-04 2009-06-15 Apparatus and method for exposing laboratory animals to a test substance WO2010002331A1 (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102138834A (en) * 2011-03-01 2011-08-03 西安交通大学医学院第一附属医院 Anesthesia device for animal experiment
CN102788868A (en) * 2012-09-04 2012-11-21 天津开发区合普工贸有限公司 Whole-body and only-nose compatible breathing toxicity test equipment
CN102935018A (en) * 2012-11-13 2013-02-20 天津开发区合普工贸有限公司 Animal experiment device for passive smoke produced by human smoking
WO2014082045A1 (en) * 2012-11-26 2014-05-30 President And Fellows Of Harvard College Plethysmograph array having signal shielding
CN104873295A (en) * 2014-08-06 2015-09-02 南通大学 Vertical type filtered carbon monoxide poisoning device capable of significantly improving working efficiency
EP2929858A1 (en) * 2014-04-10 2015-10-14 R & M Butterworth Pty Ltd. Livestock treatment method and apparatus
RU177360U1 (en) * 2017-10-18 2018-02-19 Федеральное государственное бюджетное образовательное учреждение высшего образования "Амурская государственная медицинская академия" Министерства здравоохранения Российской Федерации INHALATOR FOR LABORATORY ANIMALS WITH REGULATED LEVEL OF DELIVERY OF THE EXPECTING SUBSTANCE
RU186137U1 (en) * 2018-10-03 2019-01-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Амурская государственная медицинская академия" Министерства здравоохранения Российской Федерации Automatic inhaler for laboratory animals
RU189267U1 (en) * 2019-03-22 2019-05-17 Федеральное государственное автономное образовательное учреждение высшего образования "Дальневосточный федеральный университет" (ДВФУ) Node formation of an active substance in the inhalation installation
US10632271B1 (en) 2015-11-30 2020-04-28 Warren Matthew Leevy Versatile subject bed
US10646320B1 (en) 2014-03-07 2020-05-12 Warren Matthew Leevy Subject imaging bed
CN113009125A (en) * 2021-02-25 2021-06-22 中国科学院生态环境研究中心 Breath metabolism measurement system
RU211212U1 (en) * 2021-08-24 2022-05-25 Федеральное государственное бюджетное научное учреждение "Научно-исследовательский институт медицины труда имени академика Н.Ф. Измерова" (ФГБНУ "НИИ МТ") An inhalation device for priming animals with automatic minimization of the consumption of the active substance
CN116420629A (en) * 2023-03-16 2023-07-14 浙江大学 Multifunctional animal exposure experimental device

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4520808A (en) * 1983-03-10 1985-06-04 Stauffer Chemical Company Inhalation exposure apparatus
US4721060A (en) * 1986-07-17 1988-01-26 Battelle Memorial Institute Nose-only exposure system
US4860741A (en) * 1987-02-09 1989-08-29 Research & Consulting Co. A.G. Modular inhalation tower for laboratory animals
US5297502A (en) * 1993-05-05 1994-03-29 Jaeger Rudolf J Modular reversible-flow-past nasopulmonary respiratory dosing system for laboratory animals
US6352076B1 (en) * 1999-07-01 2002-03-05 Larry G. French Anesthesia induction chamber for small animals
US20030125633A1 (en) * 2001-07-31 2003-07-03 U.S. Army Medical Research And Materiel Command Inhalation system
EP1752111A1 (en) * 2005-08-08 2007-02-14 Olympus Corporation Anesthetizing chamber and microscope apparatus

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4520808A (en) * 1983-03-10 1985-06-04 Stauffer Chemical Company Inhalation exposure apparatus
US4721060A (en) * 1986-07-17 1988-01-26 Battelle Memorial Institute Nose-only exposure system
US4860741A (en) * 1987-02-09 1989-08-29 Research & Consulting Co. A.G. Modular inhalation tower for laboratory animals
US5297502A (en) * 1993-05-05 1994-03-29 Jaeger Rudolf J Modular reversible-flow-past nasopulmonary respiratory dosing system for laboratory animals
US6352076B1 (en) * 1999-07-01 2002-03-05 Larry G. French Anesthesia induction chamber for small animals
US20030125633A1 (en) * 2001-07-31 2003-07-03 U.S. Army Medical Research And Materiel Command Inhalation system
EP1752111A1 (en) * 2005-08-08 2007-02-14 Olympus Corporation Anesthetizing chamber and microscope apparatus

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102138834A (en) * 2011-03-01 2011-08-03 西安交通大学医学院第一附属医院 Anesthesia device for animal experiment
CN102138834B (en) * 2011-03-01 2013-04-10 西安交通大学医学院第一附属医院 Anesthesia device for animal experiment
CN102788868A (en) * 2012-09-04 2012-11-21 天津开发区合普工贸有限公司 Whole-body and only-nose compatible breathing toxicity test equipment
CN102935018A (en) * 2012-11-13 2013-02-20 天津开发区合普工贸有限公司 Animal experiment device for passive smoke produced by human smoking
CN102935018B (en) * 2012-11-13 2014-11-26 天津开发区合普工贸有限公司 Animal experiment device for passive smoke produced by human smoking
WO2014082045A1 (en) * 2012-11-26 2014-05-30 President And Fellows Of Harvard College Plethysmograph array having signal shielding
US10646320B1 (en) 2014-03-07 2020-05-12 Warren Matthew Leevy Subject imaging bed
EP2929858A1 (en) * 2014-04-10 2015-10-14 R & M Butterworth Pty Ltd. Livestock treatment method and apparatus
CN104873295A (en) * 2014-08-06 2015-09-02 南通大学 Vertical type filtered carbon monoxide poisoning device capable of significantly improving working efficiency
CN104873295B (en) * 2014-08-06 2016-08-17 南通大学 Filtered vertical type carbon monoxide poisoning device
CN104873296B (en) * 2014-08-06 2016-09-28 南通大学 Filtered vertical type carbon monoxide poisoning device
CN104873296A (en) * 2014-08-06 2015-09-02 南通大学 Operating method for up-and-down type carbon monoxide poisoning device through filtration
US10632271B1 (en) 2015-11-30 2020-04-28 Warren Matthew Leevy Versatile subject bed
RU177360U1 (en) * 2017-10-18 2018-02-19 Федеральное государственное бюджетное образовательное учреждение высшего образования "Амурская государственная медицинская академия" Министерства здравоохранения Российской Федерации INHALATOR FOR LABORATORY ANIMALS WITH REGULATED LEVEL OF DELIVERY OF THE EXPECTING SUBSTANCE
RU186137U1 (en) * 2018-10-03 2019-01-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Амурская государственная медицинская академия" Министерства здравоохранения Российской Федерации Automatic inhaler for laboratory animals
RU189267U1 (en) * 2019-03-22 2019-05-17 Федеральное государственное автономное образовательное учреждение высшего образования "Дальневосточный федеральный университет" (ДВФУ) Node formation of an active substance in the inhalation installation
CN113009125A (en) * 2021-02-25 2021-06-22 中国科学院生态环境研究中心 Breath metabolism measurement system
CN113009125B (en) * 2021-02-25 2022-03-18 中国科学院生态环境研究中心 Breath metabolism measurement system
RU211212U1 (en) * 2021-08-24 2022-05-25 Федеральное государственное бюджетное научное учреждение "Научно-исследовательский институт медицины труда имени академика Н.Ф. Измерова" (ФГБНУ "НИИ МТ") An inhalation device for priming animals with automatic minimization of the consumption of the active substance
CN116420629A (en) * 2023-03-16 2023-07-14 浙江大学 Multifunctional animal exposure experimental device
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