WO2022196602A1

WO2022196602A1 - Small animal securing device

Info

Publication number: WO2022196602A1
Application number: PCT/JP2022/011168
Authority: WO
Inventors: 政紀松崎; 鉄平蝦名
Original assignee: 国立大学法人東京大学
Priority date: 2021-03-16
Filing date: 2022-03-14
Publication date: 2022-09-22
Also published as: JP2022142149A

Abstract

In order to provide a small animal securing device having high securing position reproducibility and capable of easily and accurately securing a small experimental animal to an experimental apparatus, a small animal securing device 10 according to the present disclosure is provided with: a securing plate member 20 that is mounted on the head of a small animal A; an experimental apparatus body-side frame member 110 that allows the securing plate member 20 to be removably attached to a predetermined attachment position thereof; a positioning means 30 that determines the vertical position of the securing plate member 20 attached to the predetermined attachment position of the frame member 110; and a pressing tool 40 that presses the securing plate member 20 against the predetermined attachment position. The positioning means 30 may be configured to have a gradient part that applies a pressing component in the vertical direction to the securing plate member 20 attached to the predetermined attachment position.

Description

Small animal restraint device

The present invention relates to a small animal fixing device.

As a behavioral experiment targeting small animals such as mice and rats, the small animals are made to learn certain movements, their brains are photographed under a microscope, and changes occurring in the brain are observed. In such experiments, a device for fixing the head of the small animal is required. As a fixing device for that purpose, a plate is attached to the skull of the small animal, and the plate is attached to the column or frame of the experimental apparatus. A device configured to restrict the movement of the head by being attached is used (see Patent Document 1, for example). The plate is attached to the experimental apparatus using, for example, a mechanism (sandwiching mechanism) in which both ends of the plate are held down by a pressing plate by turning a screw.

JP 2017-131197 A

However, with the device using the above mechanism (clamping mechanism), it takes time and effort to operate until the plate is attached. In fact, when attaching the plate to the experimental apparatus, while holding the small animal trying to move with one hand, insert the plate under the pressing plate with the other hand and turn multiple screws while making fine adjustments to the appropriate position. It requires a series of operations, and it is not hard to imagine that it takes time and effort, especially when working alone, even for people other than those involved. Moreover, although the precision of the fixation position is important for clear imaging of even the smallest details of the brain with a microscope, conventional devices with the mechanism described above cannot accurately determine the fixation position of a small animal. Not only is the reproducibility of the fixing position poor, but there are also concerns about the positioning accuracy of the plate in the vertical direction.

Therefore, it is an object of the present invention to provide a small animal fixing device that has high reproducibility of fixing positions and can easily and accurately fix small experimental animals to experimental equipment.

One aspect of the present invention is a small animal fixing device for fixing a small experimental animal to a laboratory apparatus,
a fixing plate member attached to the head of a small animal;
a frame member on the side of the main body of the experimental apparatus to which the fixing plate member can be attached and detached at a predetermined attachment position;
positioning means for defining the vertical position of the fixing plate member attached to the predetermined attachment position of the frame member;
a pressing tool for pressing the fixing plate member against a predetermined mounting position;
A small animal immobilization device comprising:

According to the small animal fixing device of this aspect, the fixing plate member attached to the head of the small animal is temporarily placed by guiding it to the predetermined attachment position of the frame member. The member can be pressed into place and, in doing so, the positioning means can be used to define the vertical position of the fixing plate member. In that case, the operation is a series of conventional operations such as holding a small animal trying to move with one hand and inserting the plate under the pressing plate with the other hand and turning multiple screws while making fine adjustments so that it is in the proper position. It is extremely simple compared to In addition, although the operation is simple, the fixing plate member can be positioned at a predetermined mounting position with good reproducibility and high accuracy through cooperation between the pressing tool and the positioning means.

In the above-described small animal fixing device, the positioning means may have a sloped portion that applies a vertical pressure component to the fixing plate member attached to the predetermined attachment position.

In the small animal fixing device of the above aspect, the sloped portion may be formed on the side of the fixing plate member.

In the small animal fixing device of the above aspect, the sloped portion may be formed in the stopper for positioning the fixing plate member in a horizontal position.

A plurality of stoppers may be formed on the frame member in the small animal fixing device of the above aspect.

In the apparatus for securing a small animal as described above, one or both of the contact portions between the pressing tool and the securing plate member have a gradient that applies a vertical pressing component to the securing plate member in a state of being attached to a predetermined mounting position. A part may be formed.

In the device for fixing a small animal as described above, the pressing tool may be provided at a position that applies a pressing force to the stopper from the direction in which the fixing plate member is pressed.

The small animal fixing device of the above aspect may further comprise biasing means for biasing the pressing tool in one direction.

The pressing tool in the small animal fixing device of the above aspect may include a restricting device that restricts the movable range of the fixing plate member.

The fixing plate member in the small animal fixing device of the above aspect may be configured to be attached to a predetermined attachment position of the frame member via an attachment.

The attachment in the small animal fixing device of the above aspect may be formed in a shape that can be attached and detached by changing the orientation with respect to the predetermined attachment position of the frame member.

The attachment in the small animal fixing device of the above aspect may be provided with another positioning means for defining the vertical position of the fixing plate member.

The attachment in the small animal fixing device of the above aspect may be provided with another positioning means for defining the horizontal position of the fixing plate member.

The attachment in the small animal fixing device of the above aspect may be provided with another pressing tool for pressing the fixing plate member against another positioning means.

According to the present invention, it is possible to provide a small animal fixing device that has excellent reproducibility of fixing positions and can easily and accurately fix small experimental animals to experimental equipment.

It is a figure which shows the structural example of the experimental device in one Embodiment of this invention. Fig. 2 is a plan view of a main body side frame member showing the first embodiment of the small animal fixing device; It is the figure which looked at the frame member from the back. FIG. 4 is a plan view showing the frame member and the fixing plate member with the pressing lever opened; FIG. 4 is a plan view showing a state in which a fixing plate member is attached to a frame member; It is the figure which looked at the state which attached the plate member for fixation to the frame member from the back. FIG. 4 is a plan view showing a state in which a fixing plate member attached to a frame member is pressed by a pressing lever; It is the figure which looked at the state which pressed the fixing plate member attached to the frame member with the pressing lever from the back. FIG. 10 is a plan view showing a frame member, an attachment, and a fixing plate member on the main body side in a second embodiment of the small animal fixing device; It is the figure which looked at the attachment in FIG. 6A from the back. FIG. 10 is a plan view showing a state in which the fixing plate member is attached to the attachment with the pressing slider pulled; It is a top view which shows the state which attached the plate member for fixation to the attachment, and pressed with the pressing slider. FIG. 10 is a plan view showing how the attachment in which the movable range of the fixing plate member is restricted by the screw device is attached to the frame member. It is a top view which shows the state which attached the attachment to the frame member. It is the figure which looked at the attachment from the back.

Hereinafter, the configuration of the present invention will be described in detail based on an embodiment shown in the drawings.

In the embodiments described below, first, an outline of the overall configuration of the experimental device 1 will be described (see FIG. 1), and then an embodiment of the small animal fixing device 10 according to the present invention will be described (see FIG. 2, etc.). .

[Overview of experimental equipment]
The experimental device 1 is a device for conducting a behavioral experiment on a small animal A such as a mouse or a rat. It is configured to perform various operations such as observing changes occurring in the brain. For example, the experimental apparatus 1 of this embodiment includes a fixed table (main body of the experimental apparatus) 100, a frame member 110, a stereotactic fixed frame 120, a restrainer 130, a spout lever unit 140, a water supply unit 200, a speaker 300, and a sound stimulation unit 400. , an interface device 500, a computer 600, and software 610 (see FIG. 1), and further includes an imaging device and the like (not shown).

The fixing base 100 is the main body of the experimental device 1 and includes a base for fixing the small animal A to be tested. The frame member 110 is a member used when fixing the head of the small animal A, and includes a frame to which the fixing plate member 20 attached to the skull of the small animal A can be attached and detached (see FIG. 1, etc.). . A detailed structure of a device for attaching and detaching the fixing plate member 20 to and from the frame member 110 (the small animal fixing device 10) will be described in embodiments described later. Above the frame member 110, an imaging device such as a microscope, electrical recording, and a manipulator (not shown) for intracerebral injection are provided. A lighting device (not shown) for illuminating the vicinity of the head of the small animal A to be imaged is provided in the vicinity of the imaging device, if necessary. For convenience of explanation, in this specification, the direction in which the head of the small animal A fixed on the fixing table 100 faces is referred to as "forward", the opposite direction is referred to as "backward", and the right side of the small animal A in plan view. , the left side will be referred to as "right side" and "left side", respectively (see FIG. 1).

The stereotaxic frame 120 is a frame for stereotactically fixing a manipulator for electrical recording experiments and intracerebral injections. It is an instrument, and is composed of a curved plate or the like that holds down the back side of the small animal A and regulates its range of motion (see FIG. 1).

The spout lever unit 140 is a device that gives water as a reward when a certain condition is met, for example, when the small animal A on the fixed table 100 performs a predetermined action. In addition to water, water containing sugars, water containing artificial sweeteners, etc. may be provided as a reward. The water supply unit 200 is a device for supplying water or the like to the spout lever unit 140 . The spout lever unit 140 and water supply unit 200 are connected to a computer 600 via an interface device 500 (see FIG. 1).

The speaker 300 and the sound stimulation unit 400 are devices for giving auditory stimulation to the small animal A. The sound stimulation unit 400 is connected to the computer 600 via the interface device 500, and generates a predetermined sound from the speaker 300 according to the program (see FIG. 1). As a stimulus to be given to the small animal A, in addition to such auditory stimulating sound, it is also possible to give a visual stimulus using, for example, flashing light, or an olfactory stimulus using some kind of odor.

The computer 600 is connected to the spout lever unit 140, the water supply unit 200, and the sound stimulation unit 400, exchanges signals with each device, and causes them to perform predetermined operations as necessary. Software 610 is stored in the computer 600 of this embodiment, and it is possible to perform various kinds of control such as automatically performing experiments and aggregating data according to a predetermined program.

[First Embodiment]
A first embodiment of the small animal securing device 10 will now be described (see FIGS. 1-5B).

The small animal fixing device 10 is a device for fixing a small experimental animal A to the experimental device 1, and is configured as a suitable device especially when a mouse is used as an experimental object. The small animal fixing device 10 of this embodiment includes a fixing plate member 20, a frame member 110, a stopper (positioning means) 30, a pressing lever (pressing tool) 40, and the like (see FIG. 3, etc.).

The fixing plate member 20 is a member that fixes the small animal A to the experimental device 1 by being attached to the head of the small animal A at a predetermined attachment position P of the frame member 110 (see FIG. 3). The fixing plate member 20 itself may have the same structure as the conventional one. In this embodiment, a plate-like member having a polygonal opening 21 suitable for photographing the brain of the head of a small animal A with a microscope and made of stainless steel or the like is thin and lightweight. It is adopted as the fixing plate member 20 . Moreover, in this embodiment, the fixing plate member 20 having a shape having a side edge portion 20S and an edge portion 20F facing forward is adopted (see FIG. 3 and the like).

The frame member 110 is a member configured so that the fixing plate member 20 can be attached to and detached from the predetermined attachment position P. The frame member 110 of this embodiment is arranged at a predetermined position (the position where the head of the small animal A is fixed) on the fixing base 100 (see FIG. 1). The frame member 110 is composed of a portion that serves as the top plate and support portions (side frames, support columns, etc.) that support the portion that serves as the top plate. shows only The frame member 110 of the present embodiment is provided with a notched recess 112, and the fixing plate member 20 can be attached and detached from behind toward the recess 112 (see FIGS. 3 and 4A). ). The frame member 110 is provided with a mounting surface 114 that contacts the left and right bottom surfaces of the fixing plate member 20 (indicated by

reference numerals

22L and 22R in FIG. 3). . The mounting surface 114 may be formed at a position one step lower than the upper surface of the frame member 110 (indicated by reference numeral 113 in FIG. 2B) (see FIG. 2B).

The stopper 30 is provided so as to function as positioning means for defining the vertical position and the horizontal position of the fixing plate member 20 attached to the frame member 110 . The specific configuration of the stopper 30 is not particularly limited as long as it exhibits such a function. As a preferred example, in this embodiment, a plate-like positioning tool 31 having an inclined surface (inclined portion) 32 is attached to a frame member 110 with a screw 33, and a stopper 30 including an overhanging (forward inclined) inclined surface 32 is attached to the frame member 110. (see FIGS. 4A, 4B, etc.). By properly arranging the plurality of stoppers 30, it is possible to uniformly define the horizontal position of the fixing plate member 20 when it collides with these stoppers 30 (see FIGS. 4A, 5A, etc.). Specifically, in the present embodiment, three stoppers 30 are provided. , so that the fixing plate member 20 is positioned at the predetermined mounting position P (see FIGS. 3, 4A, etc.).

Further, by providing the stopper 30 configured as described above, a wedge-shaped guide can be formed by forming a tapered surface with the overhanging (forward inclined) inclined surface 32 and the mounting surface 114 (FIG. 2B). reference). According to such a wedge-shaped guide, a vertical pressing component can be applied to the fixing plate member 20 to give a component force to press the fixing plate member 20 toward the mounting surface 114 . , it is possible to define the horizontal position as well as the vertical position (see FIGS. 4A to 5B, etc.).

The pressing lever 40 is a member provided as a pressing tool that presses the fixing plate member 20 toward the predetermined mounting position P. The pressing lever 40 of the present embodiment is horizontally rotatable around a fulcrum 43 arranged near a predetermined mounting position P on the frame member 110 , and the stopper 30 is pushed through the pressing portion 44 . It is provided so that a pressing force acts from the direction in which the fixing plate member 20 is pressed toward (see FIGS. 4A, 5A, etc.).

Further, the pressing lever 40 is pushed in one direction, in this embodiment, in the direction of pressing the fixing plate member 20 toward the predetermined mounting position P by an urging means composed of, for example, a tension spring 42 hooked to the locking portion 45. It is pulled and biased (see FIG. 2A, etc.). The pressing lever 40 biased in this manner keeps the fixing plate member 20 pressed toward the predetermined mounting position P (see FIG. 5A). Moreover, the pressing lever 40 of the present embodiment has a structure in which the distance between the fulcrum 43 and the pressing portion 44 is relatively small, while the distance between the locking portion 45 to which the tension spring 42 is applied and the fulcrum 43 is sufficiently large. , and is configured such that a larger pressing force acts on the fixing plate member 20 due to the action of the lever. Therefore, even if the small animal A fixed to the experimental device 1 moves or acts violently, it is easy to keep the pressing lever 40 pressed so that the fixing plate member 20 does not move. Reference numeral 46 denotes a regulating projection that abuts against the pressing lever 40 and regulates the rotatable region of the pressing lever 40 in the urging direction (see FIG. 2A, etc.).

A pressing portion 44 of the pressing lever 40 that comes into contact with the fixing plate member 20 is formed with an inclined surface 41 inclined so as to overhang (forward slope) (see FIG. 2B, etc.). When the fixing plate member 20 is pressed toward the predetermined mounting position P, the inclined surface 41 exerts a vertical pressing component and provides a component force for pressing toward the mounting surface 114 . The action of the inclined surface 41 as described above, together with the action of the inclined surface 32 of the stopper 30, helps define the vertical position of the fixing plate member 20 with higher accuracy when positioning it.

A series of operations and associated movements when using the small animal immobilization device 10 as described above will be described (see FIGS. 2A to 5B). When attaching the fixing plate member 20 to the frame member 110 , first, an operator (meaning a person who conducts the experiment and his assistants) turns the pressing lever 40 counterclockwise in the figure to open it, thereby opening the pressing portion 44 . moves away from the predetermined mounting position P (see FIG. 3). In this state, the fixing plate member 20 is moved in a predetermined direction from the rear toward the predetermined mounting position P and placed on the mounting surface 114 of the frame member 110 . Furthermore, on the mounting surface 114, the fixing plate member 20 is slid until the side edge portion 20S and the edge portion 20F facing the front come into contact with the stopper 30 (the inclined surface 32 of the positioning tool 31 constituting the stopper 30). 4A and 4B), then release the hand that has been pushing the pressing lever 40 open. The pressing lever 40 automatically closed by the urging force presses the fixing plate member 20 toward each stopper 30 via the pressing portion 44 to position it at the predetermined mounting position P. As shown in FIG. At this time, the horizontal position and the vertical position of the fixing plate member 20 are defined by the action of the

inclined surfaces

32 and 41 as described above (see FIGS. 5A and 5B). The series of mounting operations described above can be completed by operating the pressing lever 40 with one hand and moving the fixing plate member 20 with the other hand. be.

[Second embodiment]
Next, a second embodiment of the small animal securing device 10 will be described (see FIGS. 6A to 10B).

The small animal fixing device 10 of this embodiment is configured as a device more suitable for fixing a small animal A, such as a marmoset, which is larger than the aforementioned mouse or the like, to the experimental device 1 . The small animal fixing device 10 of this embodiment includes a fixing plate member 20, a frame member 110, a stopper (positioning means) 30, and an attachment 50 (see FIG. 6A, etc.).

The fixing plate member 20 is attached to the head of a small animal (especially a marmoset) A and attached to a predetermined attachment position of the frame member 110 via an attachment 50, thereby attaching the small animal A to the experimental apparatus 1. It is a member to be fixed. The fixing plate member 20 itself may have the same structure as the conventional one. In this embodiment, a fixing plate member 20 having a shape and size suitable for a small animal A such as a marmoset and having a polygonal opening 21 is employed. Further, in the present embodiment, the fixing plate member 20 having a shape having a left front slant edge 23L and a right front slant edge 23R formed to abut on the stopper 51 of the attachment 50 is adopted (see FIG. 6A etc.). ).

The attachment 50 is a member that can function as a so-called adapter that matches the sizes of the relatively small fixing plate member 20 to the relatively large fixing plate member 20 (see FIG. 6A, etc.). The attachment 50 is configured to be detachable from the frame member 110, and the fixing plate member 20 is detachable from the attachment 50, for example, the front edge 50F and the left edge 50L in plan view. , right edge 50R, etc. (see FIGS. 6A, 8, etc.). The attachment 50 is provided with a mounting surface 54 in contact with a portion of the bottom surface of the fixing plate member 20 (for example, the rear surface of the portion including the vicinity of the right front bevel edge 23R), a stopper 51, a pressure slider 52, and a regulating screw. 53, etc. (see FIG. 6A, etc.) The mounting surface 54 may be formed at a position one level lower than the upper surface of the attachment 50 (shown by reference numeral 50u in FIG. 6B) (see FIG. 6B).

The stopper 51 is provided so as to function as positioning means for defining the vertical position and the horizontal position of the fixing plate member 20 . The specific configuration of the stopper 51 is not particularly limited as long as it exhibits such a function. As an example, in this embodiment, a countersunk screw is used, and the stopper 51 is configured using the inclined portion 51s of the conical seat surface of the countersunk screw (see FIGS. 6A, 6B, etc.). The stopper 51 configured using countersunk screws has a simple structure and can be easily manufactured at a low cost. Further, by appropriately arranging a plurality of stoppers 51, it is possible to uniformly define the horizontal position of the fixing plate member 20 when it collides with these stoppers 51 (see FIG. 8, etc.). Specifically, in this embodiment, three stoppers 51 are provided. , so that the fixing plate member 20 is positioned at a predetermined relative position with respect to the attachment 50 (see FIGS. 8, 9, etc.).

Further, in the stopper 51 configured as described above, a wedge-shaped guide can be configured by forming a tapered surface with the mounting surface 54 and the inclined portion 51s, which is the conical bearing surface of the countersunk screw (FIG. 6B). reference). With such a wedge-shaped guide, a vertical pressing component can be applied to the fixing plate member 20 to give a component force to press the fixing plate member 20 toward the mounting surface 54 . , it is possible to define the horizontal position as well as the vertical position (see FIGS. 9 to 10B, etc.).

The pressing slider 52 is a member provided as a pressing tool for pressing the fixing plate member 20 toward a predetermined mounting position. The pressing slider 52 of this embodiment is attached to the attachment 50 by a pin 55 so as to be able to slide relative to the attachment 50 in the front-rear direction. Correspondingly, it can be stroked in the front-rear direction (see FIG. 6A, etc.). Further, the pressing slider 52 is pulled forward by an urging means such as a tension spring 56 (see FIG. 6A, etc.), and the fixing plate member 20 is pushed to each stopper 51 via the pressing portion 52p. It is provided so as to apply a pressing force in the pressing direction (see FIGS. 6A, 10A, etc.).

In addition, the pressing portion 52p of the pressing slider 52, which is the contact portion with the fixing plate member 20, is formed with an inclined surface that is inclined so as to overhang (forward slope) (see FIG. 6A, etc.). When the fixing plate member 20 is pressed toward the predetermined mounting position, the inclined surface exerts a vertical pressing component and provides a component force for pressing toward the mounting surface 54 . The action of such an inclined surface, together with the action of the inclined portion 51s of the stopper 51, helps define the vertical position of the fixing plate member 20 with higher accuracy when positioning it.

The regulating screw 53 is attached to the pressing slider 52 as an example of means for changing the stroke width of the pressing slider 52 (see FIGS. 6A, 6B, etc.). In this embodiment, a dial screw that can be turned by hand is used as the restricting screw 53 , and its tip is positioned in the stroke area of the pressing slider 52 . The stroke width of the pressure slider 52 can be changed by turning the regulation screw 53 to change the tip position thereof, and by suppressing the stroke width, the pressure slider 52 can be prevented from sliding (FIG. 9, etc.). reference). When the stroke width of the pressing slider 52 is suppressed in this way, the movable range of the fixing plate member 20 is restricted. It is possible to prevent it from coming off (see FIG. 9, etc.).

The frame member 110 is configured so that the attachment 50 can be attached and detached at a predetermined attachment position. The frame member 110 of the present embodiment is composed of a relatively large frame so as to be more suitable for fixing a small animal A, such as a marmoset, which is larger than the aforementioned mouse, to the experimental apparatus 1 (see FIG. 6A, etc.). ), and is placed at a predetermined position (the position where the head of the small animal A is fixed) on the fixing table 100 (see FIG. 1). Note that the frame member 110 is composed of a portion that serves as the top plate and support portions (side frames, support columns, etc.) that support the portion that serves as the top plate. is the same as in the first embodiment. The frame member 110 of this embodiment is substantially L-shaped in plan view, and the attachment 50 can be attached to and detached from the concave portion 112 thereof (see FIGS. 6A, 10, etc.). The frame member 110 is provided with a mounting surface 114 in contact with the bottom surface around the front edge 50F and the right edge 50R of the attachment 50, and further provided with the stopper 30 and the pressing lever 60. As shown in FIG. The mounting surface 114 may be formed at a position one step lower than the upper surface of the frame member 110 (indicated by reference numeral 113 in FIG. 6A) (see FIG. 6A, etc.).

The stopper 30 is provided so as to function as positioning means for defining the vertical position and the horizontal position of the attachment 50 attached to the frame member 110 . The specific configuration of the stopper 30 is not particularly limited as long as it exhibits such a function. In this embodiment, a plate-like positioning tool 31 having an inclined surface (inclined portion) 32 is attached to a frame member 110 with a screw 33 to form a stopper 30 including an overhanging (forward inclined) inclined surface 32 . (See FIG. 6A, FIG. 10A, etc.). By appropriately arranging the plurality of stoppers 30, it is possible to uniformly define the horizontal position of the attachment 50 when it collides with these stoppers 30 (see FIG. 10A, etc.). Specifically, in the present embodiment, three stoppers 30 are arranged, one of which is at a position where the left edge 50L of the attachment 50 abuts, and two of which are at a position where the front edge 50F abuts, The attachment 50 is positioned at a predetermined attachment position (see FIGS. 6A, 10A, etc.).

Further, by providing the stopper 30 configured as described above, a wedge-shaped guide can be formed by forming a tapered surface with the overhanging (forward inclined) inclined surface 32 and the mounting surface 114 (FIG. 6A). etc.). According to such a wedge-shaped guide, a vertical pressing component can be applied to the attachment 50 to apply a component force to press the attachment 50 toward the mounting surface 114. It is possible to define a horizontal position as well as a vertical position (see FIG. 10A, etc.).

The pressing lever 60 is a member provided as a pressing tool for pressing the attachment 50 toward a predetermined mounting position. The pressing lever 60 of this embodiment is provided so as to be able to rotate in the horizontal direction around a fulcrum 63 on the frame member 110 , and the pressing portion 64 is in the direction in which the attachment 50 is pressed toward the stopper 30 . It is provided so as to apply a pressing force from (see FIG. 6A, FIG. 10A, etc.).

Also, the pressing lever 60 is provided with a tension spring 62 and a dial screw 67 (see FIG. 6A, etc.). One end of the tension spring 62 is hooked on the frame member 110 and the other end is hooked on, for example, the locking portion 65 . It is pulled and biased so as to rotate in the direction (see FIG. 6A, etc.). The tip of the dial screw 67 abuts against the frame member 110, and by increasing the amount of protrusion of the threaded portion from the pressing lever 60, the pressing lever 60 can be moved in one direction. It is provided so as to rotate in a direction approaching the position (see FIG. 6A, etc.). By further turning the dial screw 67 to increase the amount of protrusion of the threaded portion, the pressing portion 64 can be pressed against the attachment 50 and fixed at the predetermined mounting position (see FIG. 10A, etc.).

A pressing portion 64 of the pressing lever 60 that comes into contact with the attachment 50 is formed with an inclined surface 61 inclined so as to overhang (forward slope) (see FIG. 6A, etc.). When the attachment 50 is pressed toward the predetermined mounting position, the inclined surface 61 exerts a vertical pressing component and provides a force component for pressing the mounting surface 114 . The action of the inclined surface 61 as described above, together with the action of the inclined surface 32 of the stopper 30, helps define the vertical position of the attachment 50 more accurately when positioning it. Although not shown in detail, an inclined surface 58 corresponding to the inclined surface 61 of the pressing portion 64 may be provided in a portion of the attachment 50 with which the pressing portion 64 abuts (FIG. 6A). etc.).

A series of operations and accompanying movements when using the small animal fixing device 10 as described above will be described (see FIGS. 6A to 10B).

First, when attaching the fixing plate member 20 to the attachment 50, the worker rotates the regulation screw 53 counterclockwise in advance to reduce (loosen) the projection amount of the tip of the regulation screw 53. is pulled backward in the drawing and shifted (see Fig. 7). As a result, the pressing portion 52p of the pressing slider 52 shifts in the direction away from the predetermined mounting position and is retracted. In this state, the fixing plate member 20 is directed toward the predetermined mounting position from behind in a predetermined direction. A portion of the rear surface of the attachment 50 is placed on the mounting surface 54 of the attachment 50, and the left front slant edge 23L and the right front slant edge 23R are respectively placed on the mounting surface 54 to form the stopper 51 ( (see FIG. 8), and then release the hand holding down the pressure slider 52 . The pressing slider 52 automatically slides forward in the figure by the biasing force of the tension spring 56, presses the fixing plate member 20 toward each stopper 51 via the pressing portion 52p, and positions it at the predetermined mounting position ( See Figure 8). At this time, the horizontal and vertical positions of the fixing plate member 20 with respect to the attachment 50 are controlled by the wedge action of the inclined portions 51s of the stoppers 51 and the inclined surfaces of the pressing portions 52p of the pressing sliders 52 as described above. is defined (see FIG. 8, etc.). The series of mounting operations described above can be completed by operating the pressure slider 52 with one hand and moving the fixing plate member 20 with the other hand. be.

By rotating the previously loosened restriction screw 53 clockwise, bringing its tip into contact with the pressing slider 52, and further tightening it, the pressing slider 52 is restricted from sliding. can further press the fixing plate member 20 with the pressing portion 52p. As described above, this makes it possible to prevent the fixing plate member 20 from rattling or coming off the attachment 50 (see FIG. 9).

Subsequently, when attaching the attachment 50 to the frame member 110, the operator moves the attachment 50 in a predetermined direction from the obliquely rearward direction toward a predetermined attachment position of the frame member 110, and a part of the bottom surface (the front edge 50F or the like) is moved. The bottom surface around the right edge portion 50R) is placed on the mounting surface 114 of the frame member 110, and on the mounting surface 114, the front edge portion 50F and the left edge portion 50L respectively form the stoppers 30. The attachment 50 is slid until it comes into contact with the inclined surface 32 of the positioning tool 31 (see FIG. 10A). Then, the dial screw 67 is turned clockwise (see FIG. 10B), the pressing lever 60 is rotated clockwise in plan view, and the pressing portion 64 is pressed against (the inclined surface 58 of) the attachment 50 to fix it at the predetermined mounting position. (See FIGS. 10A and 10B). By doing so, the attachment 50 can be pressed toward each stopper 30 and positioned at the predetermined mounting position. Also, at this time, the horizontal position and the vertical position of the attachment 50 are defined by the action of the

inclined surfaces

32 and 61 described above (see FIG. 10A). Moreover, since the positioning operation of the attachment 50 can be completed simply by turning the dial screw 67 with the attachment 50 attached, the attachment operation itself can be performed simply and in a short time.

It should be noted that the attachment 50 as described in the present embodiment may be formed in a shape that can be attached and detached by changing the orientation with respect to the predetermined attachment position of the frame member 110 . To give an example, the attachment 50 having a substantially L shape has been described in the present embodiment (see FIG. 6A, etc.). For example, the attachment 50 can be attached to the frame member 110 by rotating it clockwise by 90°. The small animal fixing device 10 that can be attached to and detached from the frame member 110 by changing the direction of the attachment 50 in this way is convenient, for example, when it is desired to change the direction of the small animal A (head) and take an image during an experiment.

[Action, etc.]
As described above, according to the small animal fixing device 10 of the first and second embodiments, the fixing plate member 20 attached to the head of the small animal A is directly attached to the predetermined attachment position of the frame member 110. Alternatively, positioning can be performed with high reproducibility and high precision indirectly via the attachment 50 . Moreover, the work for attaching the fixing plate member 20 to the frame member 110 is extremely simple compared to a series of operations in the conventional apparatus, and while the operation is simple, various pressing tools and positioning means can be used. By working together, the fixing plate member 20 can be positioned at a predetermined mounting position with high accuracy. In particular, in each of the aspects described in the above embodiments, the stopper arranged to form two or more sides (constituting a part of the tapered surface to form a wedge-shaped guide, defining the vertical position/horizontal position) (i.e., the portion of the frame member 110 provided with the stopper 30 or the portion of the attachment 50 provided with the stopper 51), and these frame portions Of these, a mechanism (pressing mechanism using various pressing tools such as pressing lever 40, pressing slider 52, pressing lever 60, etc.) that applies pressure from a diagonal direction to one corner where two sides intersect with a stopper realizes such an action. It can be said that the configuration is simple, effective, and practical.

Although the above-described embodiment is a preferred example of the present invention, it is not limited to this, and various modifications can be made without departing from the scope of the present invention. For example, in each of the above-described embodiments, the case where the stoppers (the stopper 30 of the frame member and the stopper 51 of the attachment 50) are provided with the inclined portions (the inclined surface 32 and the inclined portion 51s) has been described. Alternatively, or in conjunction with these arrangements, the edge of the fixation plate member 20 may be beveled to form a wedge-shaped guide similar to that described above. Based on the same idea, the portion of the fixing plate member 20 that receives the pressing force by contacting the pressing tool (the pressing lever 40, the pressing slider 52, etc.) may be provided with a slope. Alternatively, based on a similar idea, the edge of the attachment 50 may be sloped.

The present invention is suitable for application to a small animal fixing device for fixing a small experimental animal to an experimental apparatus.

Reference Signs List 1 Experimental apparatus 10 Small animal fixing device 20 Fixing plate member 20F Forward facing edge 20S Side edge 21

Openings

22L, 22R Left and right bottom surfaces 23L Left front bevel edge 23R Right front bevel Edge 30... Stopper (positioning means)
31... Positioning tool 32... Inclined surface (inclined portion)
33... Screw 40... Pressing lever (pressing tool)
41 ... Inclined surface (slope portion)
42 ... tension spring (biasing means)
43... Fulcrum 44... Pressing part 45... Locking part 46... Control projection 50... Attachment 50F... Front edge 50L... Left edge 50R... Right edge 51... Stopper provided on attachment (perpendicularity of fixing plate member) another positioning means to define the directional/horizontal position)
51s... Inclined portion (gradient portion)
52 ... A pressing slider (another pressing tool) provided on the attachment
52h... Long hole 52p... Pressing portion 53... Regulating screw (regulating device)
54... Placement surface 55... Pin 56... Extension spring (biasing means)
58... Inclined surface 59... Virtual frame piece 60... Pressing lever (pressing tool) provided on the attachment
61 ... Inclined surface (slope portion)
62... Tension spring 63... Fulcrum 64... Pressing part 65... Locking part 67... Dial screw 100... Fixed base (main body of experimental apparatus)
REFERENCE SIGNS LIST 110 Main body frame member 112 Recess 113 Upper surface 114 Placement surface 120 Stereotactic frame 130 Restrictor 140 Spout lever unit 200 Water supply unit 300 Speaker 400 Sound stimulation unit 500 Interface device 600 Computer 610...Software A...Small animal P...Predetermined mounting position

Claims

A small animal fixing device for fixing a small experimental animal to an experimental apparatus,
a fixing plate member attached to the head of the small animal;
a frame member on the side of the main body of the experimental device that allows the fixing plate member to be attached to and detached from a predetermined mounting position;
positioning means for defining a vertical position of the fixing plate member attached to the predetermined attachment position of the frame member;
a pressing tool for pressing the fixing plate member against the predetermined mounting position;
A small animal restraint device comprising:
The device for fixing a small animal according to claim 1, wherein the positioning means has a sloped portion that applies a vertical pressure component to the fixing plate member attached to the predetermined attachment position.
The small animal fixing device according to claim 2, wherein the sloped portion is formed on the side portion of the fixing plate member.
The device for fixing a small animal according to claim 2, wherein the inclined portion is formed in a stopper that positions the horizontal position of the fixing plate member.
The small animal fixing device according to claim 4, wherein a plurality of said stoppers are formed on said frame member.
At one or both of the contact portions between the pressing tool and the fixing plate member, a sloped portion is formed to apply a vertical pressing component to the fixing plate member mounted at the predetermined mounting position. A small animal immobilization device according to any one of claims 3 to 5.
The apparatus for fixing a small animal according to claim 4 or 5, wherein the pressing tool is provided at a position that applies a pressing force to the stopper from the direction in which the fixing plate member is pressed.
The small animal fixing device according to any one of claims 1 to 7, further comprising biasing means for biasing the pressing tool in one direction.
The small animal fixing device according to any one of claims 1 to 8, wherein the pressing tool includes a restricting device that restricts the movable range of the fixing plate member.
The small animal fixing device according to any one of claims 1 to 9, wherein said fixing plate member is configured to be attached to said predetermined attachment position of said frame member via an attachment.
The small animal fixing device according to claim 10, wherein the attachment is formed in a shape that can be attached to and detached from the predetermined attachment position of the frame member with different orientations.
A small animal immobilization device according to claim 10 or 11, wherein said attachment comprises further positioning means for defining the vertical position of said immobilization plate member.
A small animal immobilization device according to claim 10 or 11, wherein said attachment comprises further positioning means for defining the horizontal position of said immobilization plate member.
The small animal fixing device according to claim 13, wherein the attachment comprises another pressing tool for pressing the fixing plate member against the another positioning means.