JP3215859U - Fatigue model animal production device - Google Patents

Abstract

A fatigue model animal production apparatus capable of efficiently and easily producing a fatigue model animal for a medical experiment suitable for a research purpose is provided. A treadmill 16 having a conveyor-type running road surface 16a and causing a small animal S to walk forward is provided by moving the running road surface 16a backward. A front wall 20 is provided that surrounds the treadmill 16 and prevents the small animal S from descending from the road surface 16a. An electrode 18a is installed at the rear end portion 16a (2) of the running road surface 16a, and an electrical stimulation device 18 that applies electrical stimulation that makes the small animal S uncomfortable is provided to the small animal S in contact with the electrode 18a. A position detection sensor 22 for detecting where the small animal S is on the road surface 16a is provided. [Selection] Figure 2

Description

  The present invention relates to a fatigue model animal production apparatus for producing stress model animals for medical experiments by applying stress to small animals such as mice.

  Conventionally, as this type of device, as disclosed in Patent Document 1, for example, there has been a small animal breeding device for producing a model animal suitable for studying chronic stress-related sleep disorders. This small animal breeding apparatus includes a running wheel in which a rotating wheel rotates when the small animal walks along the inner peripheral surface of the rotating wheel, a driving device for the rotating wheel that is detachably attached to the rotating wheel, and a movement of the small animal. And a sensor for detecting. When the sensor output signal is analyzed and it is determined that the small animal is moving, the driving device is disconnected from the rotating wheel, and if the small animal does not move for a certain period of time (determining that it is asleep), the driving device Rotate the wheel to awaken the small animal. By continuing this operation, it is possible to continuously apply stress to the small animal confined in the rotating wheel and to create a sleep disorder model animal.

  Although the field is different from that of a fatigue model animal production device, as disclosed in Patent Document 2, it includes a conveyor-type treadmill and a video camera installed below the treadmill, and forcibly walks small animals on the treadmill. In addition, there is a foot motion analysis system that analyzes the foot movements of small animals with a video camera and analyzes whether or not there is an abnormal walking.

JP 2017-205083 A JP 2003-250780 A

  If too much stress is applied to a small animal when creating a fatigue model animal, it will not be possible to obtain a fatigue model animal that suits the purpose of the study, so make appropriate adjustments to the strength of the stress and judgment of when to stop applying stress. Becomes important.

  However, since the small animal breeding device of Patent Document 1 does not have means for detecting the fatigue level of the small animal that is stressed in the rotating wheel as data, is the strength of the stress applied to the small animal appropriate? It is impossible to objectively judge whether the grant should be stopped. In addition, small animals are always in a certain position (the lowest position in the rotating wheel) and only move their limbs, and there is no dynamic movement to move around, so this is also the reason why it is difficult to judge the fatigue level of small animals It has become.

  In addition, like the foot motion analysis system of Patent Document 2, a method of capturing the movement of a small animal on a treadmill using a video camera and analyzing the image data in detail to grasp the fatigue level of the small animal is conceivable. . However, in order to objectively analyze image data, it is necessary to devise a program for analyzing complex algorithms, etc., and the cost increase due to the installation of a video camera is also large. It is difficult to apply to a model animal production device.

  The present invention has been made in view of the above-described background art, and an object of the present invention is to provide a fatigue model animal production apparatus that can efficiently and easily produce a fatigue model animal for a medical experiment suitable for a research purpose.

  The present invention is an apparatus for producing a fatigue model animal for medical experiments, having a conveyor-type running road surface, and moving the running road surface in a backward direction to allow a small animal to walk forward. And an enclosure wall that surrounds the treadmill and prevents small animals from getting off the road surface, and an electrode is installed at a rearward end of the road surface. A fatigue model animal production apparatus comprising: an electrical stimulation device that applies electrical stimulation that makes a small animal unpleasant; and a position detection sensor that detects a position on the road surface of the small animal.

  The position detection sensor is preferably an infrared temperature sensor. Moreover, it is preferable to provide an inclination angle adjusting mechanism for adjusting the inclination angle in the front-rear direction on the road surface. Furthermore, it is preferable to provide a data display device that obtains an output signal of the position detection sensor, creates data for judging the fatigue level of the small animal, and displays the data.

  The fatigue model animal production apparatus of the present invention applies stress by forcibly walking a small animal with a treadmill, and a sensor for position detection that indicates where the small animal is on the traveling path while the stress is being applied. Therefore, it is possible to objectively grasp the fatigue level of small animals by analyzing the output signal of the position detection sensor. Therefore, it is possible to appropriately determine the timing to stop applying stress to a small animal, and it is possible to easily create a fatigue model animal that meets the research purpose.

  In addition to changing the moving speed of the road of the treadmill, it is possible to adjust the strength of the stress according to the constitution of the small animal by providing a mechanism that changes the inclination angle in the front-rear direction of the road. It is possible to produce a fatigue model animal more efficiently.

It is a front view (a) and (b) which show the appearance of one embodiment of the fatigue model animal preparation device of the present invention. It is a front view which shows the internal structure of the fatigue model animal production apparatus of this embodiment. It is graph (a), (b) which shows the data for judging the fatigue degree of the small animal created from the output signal of the position detection sensor. It is graph (a), (b) which shows the data for judging the fatigue degree of the small animal created from the output signal of the position detection sensor.

  Hereinafter, an embodiment of a fatigue model animal producing apparatus of the present invention will be described based on the drawings. The fatigue model animal production apparatus 10 of this embodiment is an apparatus for a small animal S such as a mouse. As shown in FIGS. 1A and 1B, a rectangular parallelepiped transparent casing 12 and a casing A housing support mechanism 14 that supports the body 12 is provided. A treadmill 16 having a conveyor-type running road surface 16 a is installed inside the housing 12.

  As shown in FIG. 2, the treadmill 16 forms a running road surface 16a by stretching an endless belt 16c between a pair of front and rear pulleys 16b. Then, the driving device 16d moves the road surface 16a in the backward direction (left direction in FIG. 2), thereby forcibly walking the small animal S on the road surface 16a in the forward direction (right direction in FIG. 2).

  An electrical stimulation device 18 is provided near the rear end portion 16a (2) of the running surface 16a, and an electrode 18a of the electrical stimulation device 18 is disposed at the rear end portion 16a (2). The electrical stimulation device 18 is a device that applies electrical stimulation that makes the small animal S uncomfortable with respect to the small animal S in contact with the electrode 18a.

  A pair of side walls of the housing 14 are disposed close to the left and right sides of the running road surface 16a, and a front wall 20 is provided at the front end portion 16a (1). The side wall and the front wall 20 of the housing 14 are enclosure walls that prevent the small animal S from descending from the runway surface 16a.

  A position detection sensor 22 is installed above the rear end portion 16a (2). The position detection sensor 22 is an infrared temperature sensor that can sense a heat source (body temperature of the small animal S) with a downward spread of about 60 degrees, and detects that the small animal S is in the region A close to the rear end 16a (2). can do.

  As shown in FIG. 1, the housing support mechanism 14 includes a shaft support member 14 a that supports the end portion of the bottom surface of the housing 14 and a jack member 14 b that supports the center portion of the bottom surface of the housing 14. By extending or contracting the jack member 14b, the inclination angle in the front-rear direction of the road surface 16a can be changed (inclination angle adjusting mechanism).

  As described above, since the runway surface 16a is moving toward the rear end portion 16a (2), the small animal S is resting at one place on the runway surface 16a and the body comes into contact with the electrode 18a. End up. Therefore, the small animal S is reluctant to contact the electrode 18a and tries to keep walking forward on the road surface 16a. That is, the small animal S is forced to walk, and a constant stress can be continuously applied to the small animal S. The strength of the stress can be variably adjusted by changing the running speed (moving speed of the running road surface 16a) or changing the inclination angle of the running road surface 16a by the running road surface tilting mechanism 14.

  In addition, the fatigue model animal production apparatus 10 includes a data display device (not shown). The data display device is a device that acquires an output signal of the position detection sensor 22, creates data for determining the fatigue level of the small animal S, and displays the data.

  The inventor prepared two healthy small animals S (S1, S2), put them in the fatigue model animal production apparatus 10, and conducted a forced walking test. The test conditions were such that the inclination angle of the road surface 16a was zero (almost horizontal), the travel speed was 15 m / min, and the test time was about 210 minutes.

  FIG. 3 and FIG. 4 are data created by the data display device, and are obtained by graphing the behavior of the small animal S from the start to the end of the test by obtaining the output signal of the position detection sensor 22. In the upper graph, the right vertical axis is the time ratio when the sensor is ON, and the ratio of the time during which the small animal S is in the region A close to the rear end portion 16a (2) is represented by a bar graph in increments of 2 minutes. In the lower graph, the right vertical axis is the number of times the sensor is turned on, and the number of times (the number of samplings) detected that “the small animal S is in the region A” is represented by a bar graph in increments of 2 minutes.

  FIG. 3 shows data of the small animal S1. In the case of the small animal S1, it can be seen that after about 120 minutes have passed since the start of applying the stress, the number of times the sensor is turned on increases on average and the fatigue of the small animal S1 has accumulated. And when 200 minutes pass, it turns out that the time ratio of sensor ON became high rapidly, and the willingness to walk was lost after being considerably tired.

  FIG. 4 shows data of the small animal S2. In the case of the small animal S2, the number of times the sensor is turned on is slightly increased after about 120 minutes from the start of applying stress, but it is not as remarkable as the small animal S1. Also, the sensor ON time ratio did not increase after 210 minutes. This is considered to be because the small animal S2 is less likely to accumulate fatigue than the small animal S1.

  The data shown in FIG. 3 and FIG. 4 are very effective for producing a fatigue model animal for medical experiments that suits the research purpose. For example, the fatigue level of a fatigue model animal suitable for the research purpose is “the fatigue level when the number of sensor ONs starts to increase on average” or “the fatigue level when the time ratio of the sensor ON suddenly increases” If it is known in advance as in the above, it is possible to easily recognize the timing at which the application of stress should be stopped by creating data as shown in FIGS. 3 and 4 in real time. In addition, for an individual who does not easily reach the target fatigue level, the strength of the stress can be increased by increasing the moving speed of the road surface 16a or tightening the inclination angle. The time to reach the degree can be shortened.

  As described above, the fatigue model animal production apparatus 10 applies stress by forcibly walking the small animal S with the treadmill 16, and while the stress is applied, the position of the small animal S on the traveling path 16a. The position detection sensor 22 detects in real time whether the user is in the vehicle. By analyzing the output signal of the position detection sensor 22, the fatigue level of the small animal S can be objectively grasped. Therefore, it is possible to appropriately determine the timing for stopping the application of stress to the small animal S, and it is possible to easily create a fatigue model animal that meets the research purpose.

  Further, by changing the moving speed of the running path 16a of the treadmill 16 or changing the inclination angle of the running path surface 16a by the housing support member 14, the strength of the stress is adjusted according to the constitution of the small animal. It is possible to efficiently produce a fatigue model animal.

  Since the configuration is such that the “position where the small animal S is present” is detected and analyzed for the fatigue level of the small animal S, an inexpensive position detection sensor such as an infrared temperature sensor can be used, and the increase in the cost of the apparatus can be kept small. .

  In addition, the fatigue model animal production apparatus of this invention is not limited to the said embodiment. For example, the “data for determining the fatigue level of a small animal” displayed by the data display device is the “graph of the time ratio of sensor ON in area A” or “number of times sensor ON in area A” shown in FIGS. The graph is not limited to the above graph, and can be appropriately changed according to the purpose. In the case of the fatigue model animal production apparatus 10 described above, the behavior of the small animal S is detected only when the small animal S enters the region A (or when it is in the region A). For example, FIG. If the position detection sensors 22 are also installed in the regions B and C to detect the behavior when entering the regions B and C, it becomes possible to analyze the fatigue level of small animals in more detail.

  In addition, a sensor other than the infrared temperature sensor may be used as the position detection sensor. The housing support member 14 includes an inclination angle adjustment mechanism that adjusts the inclination angle of the road surface 16a. However, if the adjustment of the inclination angle is unnecessary, the inclination angle adjustment mechanism may be omitted. Moreover, the inside of the housing 14 may be divided into a plurality of rooms, and a treadmill, an electrical stimulation device, or the like may be installed for each room, so that a plurality of fatigue model animals can be manufactured simultaneously.

10 Fatigue model animal production device 12 Housing (enclosure wall)
14 Housing support member (tilt angle adjustment mechanism)
16 Treadmill 16a Road surface 18 Electrical stimulation device 18a Electrode 20 Front wall (enclosure wall)
22 Position detection sensor

Claims (4)

An apparatus for producing a fatigue model animal for medical experiments,
A treadmill that has a conveyor-type running surface, and that causes the small animals to walk forward by moving the running surface backwards;
An enclosure wall that surrounds the treadmill and prevents small animals from getting off the track surface;
An electrode is installed at the rearward end of the road surface, and an electrical stimulation device that applies electrical stimulation that makes the small animal unpleasant with respect to the small animal in contact with the electrode;
An apparatus for producing a fatigue model animal, comprising: a position detection sensor that detects where the small animal is on the road surface.   The fatigue model animal production apparatus according to claim 1, wherein the position detection sensor is an infrared temperature sensor.   The fatigue model animal production apparatus according to claim 1 or 2, further comprising an inclination angle adjustment mechanism for adjusting an inclination angle in the front-rear direction of the road surface.   The fatigue model animal production apparatus according to any one of claims 1 to 3, further comprising a data display device that obtains an output signal of the position detection sensor to generate data for judging a fatigue level of a small animal and displays the data. .

Images