A standard cutting device and cutting method for the isolated brain tissue of experimental mice

Abstract

The present invention discloses a standard cutting device for the ex vivo brain tissue of experimental mice, which includes a cutting frame and a bottom plate rotatably arranged inside it. A positioning and adjusting device, an angle adjusting device and a cutting method are provided on the bottom plate. The brain tissue is positioned by the positioning and adjusting device and the optic chiasm stage, so that it is installed and placed at a predetermined position. The brain tissue is rotated to a set angle range by the angle adjusting device in combination with the angle positioning line on the side wall of the cutting frame, and the cutting of the three-dimensional brain tissue can be realized through the slicing seam, obtaining a standard coronal plane of the brain tissue. The present invention combines the morphological characteristics of the animal brain, and through calculation, it can accurately determine the spatial positioning of the animal brain and vertically cut it, ensuring that the subsequent frozen section is matched with the brain coronal section of the standard brain atlas in medical experiments. The overall structure is convenient to operate and low in cost, greatly improving the standardization degree of brain sections.

Description

Technical Field

[0001] The present invention relates to the field of biomedical experiments, and particularly to a standard cutting device and method for excised brain tissue of experimental mice. Background Art

[0002] One of the most active research hotspots in the international biomedical research field is neuroscience research. Whether in terms of structure or function, the brain is the most complex organ in the human body. The brain controls the basic physiological activities and behaviors of humans, and is also the organ for higher brain functions such as psychology and cognition formation. The research on the structure and function of the brain not only helps to uncover the mysteries of the brain, but also promotes the research and application of artificial intelligence; brain research can also reveal the pathogenesis of major brain diseases and provide ideas and treatment strategies for treating brain diseases.

[0003] In brain research, almost all laboratories use rodents (such as rats and mice), and most research results are analyzed with reference to the standard brain stereotaxic atlases of rats and mice. When making the standard brain atlas, after precise stereotaxic positioning based on the morphological characteristics of the skull and brain surface, the brain is then sectioned, as shown in Figure 1 a. On the resulting coronal section of the brain, the morphology, position, and adjacent structures of each nucleus are relatively constant. In actual research work, when researchers are engaged in brain research, they need to take out and fix the brain of large / small mice and then perform coronal sectioning, and then describe, analyze, and calculate their research results and data with reference to the standard brain atlas.

[0004] Therefore, applying sectioning technology to obtain brain sections of large / small mice that match the standard brain atlas is the basis for correctly analyzing research results. To obtain coronal brain sections, after taking out the brain tissue, researchers need to transect the brain tissue under naked-eye conditions, and then place the severed brain on a freezing table for sectioning. Among them, the following two factors make the coronal brain sections obtained by the above method not in the same standard brain plane in the dorsal / ventral or left / right directions, that is, they cannot match the coronal section shown in the standard brain atlas. First, under naked-eye conditions, it is very difficult to ensure that the left / right side or dorsal / ventral side of the brain section formed after transection is in the same plane. After such a brain section adheres to the freezing table, the cut brain section will inevitably deviate from the standard brain section, as shown in Figure 1 b. Second, since the relative positions between the cranial nerve nuclei on the coronal section are mostly in the order of micrometers, after adhering the non-standard transected brain to the freezing table, it is almost impossible to adjust the positional relationship between the brain block and the cutting knife by naked-eye observation to obtain a standard brain section. Therefore, it is very difficult to obtain a coronal brain section that matches the standard brain atlas by sectioning the excised brain under naked-eye conditions in vitro. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention provides a standard cutting device for the isolated brain tissue of experimental mice. First, stereotactic positioning is performed on the isolated brain, and then the isolated brain is cut to obtain a brain coronal section that matches the standard brain atlas.

[0006] The present invention is realized through the following technical solutions:

[0007] A standard cutting device for the isolated brain tissue of experimental mice includes a transparent sectioning frame, a bottom plate, a positioning and adjusting device, and an angle adjusting device;

[0008] The bottom plate is arranged in the sectioning frame. One end of the bottom plate is rotatably connected to the sectioning frame, and the other end of the bottom plate is connected to the angle adjusting device. A chiasmatic platform for positioning the brain tissue is arranged on the bottom plate. The positioning and adjusting device is arranged on the bottom plate and is located at the end far from the rotation of the bottom plate. Angle positioning lines are arranged on the side wall of the sectioning frame. The intersection point of the projection of the center of the top surface of the chiasmatic platform on the side wall of the sectioning frame and the angle positioning line coincides. A vertical sectioning slit is also arranged on the side wall of the sectioning frame, and the sectioning slit intersects with the angle positioning line;

[0009] The positioning and adjusting device includes a fixing plate, a positioning rod, and a bidirectional adjusting device. The bidirectional adjusting device is slidably connected to the fixing plate, and the positioning rod is connected to the bidirectional adjusting device. The bidirectional adjusting device is used to adjust the axial position and height of the positioning rod. A positioning needle is arranged at the end of the positioning rod. When the positioning needle is located at the contact part of the left and right cerebral cortices of the brain tissue and the positioning needle is within the range of the angle positioning line, sectioning the brain tissue along the sectioning slit can obtain a coronal section of the brain tissue.

[0010] Preferably, the angle adjusting device includes a connecting part and an angle adjusting rod. The connecting part is arranged at the end of the bottom plate and is located at the end far from the chiasmatic platform. The angle adjusting rod is vertically installed on the rear end plate of the sectioning frame. The lower end of the angle adjusting rod is rotatably connected to the connecting part, and the angle adjusting rod can move up and down along the sectioning frame.

[0011] Preferably, a clamping groove is arranged at the end of the connecting part. Strip-shaped guide holes are arranged on the two side walls of the clamping groove. A connecting rod is arranged in the guide holes. The lower end of the angle adjusting rod is rotatably connected to the connecting rod.

[0012] Preferably, a rotating shaft is arranged in the sectioning frame. The chiasmatic platform is arranged at the width center of the bottom plate, and the axis of the chiasmatic platform is vertically and intersectingly arranged with the axial direction of the rotating shaft.

[0013] Preferably, a horizontal calibration line is arranged on the side wall of the sectioning frame for calibrating the horizontal state of the bottom.

[0014] Preferably, the angle positioning lines are three lines, and their horizontal angles are 50°, 57°, and 60° respectively.

[0015] Preferably, the bidirectional adjustment device includes a lifting adjustment rod and a slider;

[0016] The fixed plate is vertically arranged on the bottom plate. A guiding groove is provided on the fixed plate. The slider is arranged in the guiding groove. The lifting adjustment rod is rotationally connected to the fixed plate by a thread. The lower end of the lifting adjustment rod is located in the guiding groove and is rotationally connected to the top of the slider. The upper end of the lifting adjustment rod extends to the top of the fixed plate. Rotating the lifting adjustment rod can make the slider slide up and down along the guiding groove.

[0017] Preferably, a horizontal adjustment hole is provided on the slider. A positioning rod is arranged in the horizontal adjustment hole. The positioning rod can move along the horizontal adjustment hole. A positioning block is arranged on one side of the slider. The end of the positioning rod passes through the positioning block and extends out. A limit pin is provided on the positioning block for limiting the horizontal position of the positioning rod.

[0018] Preferably, a visual plate is further provided at the end of the positioning rod and is in the same plane as the positioning needle. The visual plate is close to the inner side wall of the cutting frame.

[0019] A cutting method for a standard cutting device for an experimental mouse's ex vivo brain tissue includes the following steps:

[0020] Step 1: Place the ex vivo brain tissue on the bottom plate in a horizontal state, and place the optic chiasm of the brain tissue on the optic chiasm platform of the bottom plate;

[0021] Step 2: Adjust the position of the brain tissue so that the midline in the rostrocaudal direction of the ventral surface of the brain tissue coincides with the axial center line of the bottom plate, and at the same time, make the sagittal suture on the dorsal surface of the brain tissue coincide with the axis of the positioning rod;

[0022] Step 3: Adjust the position of the positioning needle so that the tip of the positioning needle touches the contact part of the left and right cerebral cortices of the brain tissue;

[0023] Step 4: Adjust the angle of the bottom plate so that the tip of the positioning needle is within the range of the angle positioning line;

[0024] Step 5: Insert a blade into the slicing seam, and the blade moves down along the slicing seam to cut the brain tissue.

[0025] Compared with the prior art, the present invention has the following beneficial technical effects:

[0026] An experimental mouse ex vivo brain tissue standard cutting device provided by the present invention includes a cutting frame and a bottom plate rotatably arranged inside it. A positioning and adjusting device and an angle adjusting device are arranged on the bottom plate. The brain tissue is positioned through the positioning and adjusting device and the optic chiasm platform, so that it is placed at a predetermined position. The brain tissue is rotated to a set angle range through the angle adjusting device and in combination with the angle positioning line on the side wall of the cutting frame, and the three-dimensional brain tissue can be cut through the slicing seam to obtain a standard coronal plane of the brain tissue. The present invention combines the morphological characteristics of the animal brain, and through calculation, it can accurately determine the spatial positioning of the animal brain and vertically cut it, ensuring that the subsequent frozen section is matched with the brain coronal section of the standard brain atlas in medical experiments, and ensuring the unbiasedness and accuracy of brain structure analysis. The overall structure is convenient to operate and low in cost, greatly improving the standardization degree of brain sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of cutting the brain tissue of an experimental mouse;

[0028] Among them, Figure 1 a is a schematic diagram of standard cutting of the brain tissue of large and small mice; Figure 1 b is a schematic diagram of incorrect cutting of the brain tissue of large and small mice;

[0029] Figure 2 It is a schematic diagram of the structure of the ex vivo brain tissue standard slicing device of the present invention;

[0030] Figure 3 It is a schematic diagram of the internal structure of the ex vivo brain tissue standard slicing device of the present invention;

[0031] Figure 4 It is a schematic diagram of the structure of the bottom plate of the present invention;

[0032] Figure 5 It is a schematic diagram of the structure of the cutting frame of the present invention;

[0033] Figure 6 It is the front view of the ex vivo brain tissue standard slicing device of the present invention;

[0034] Figure 7 It is a schematic diagram of the structure of the adjusting device of the present invention;

[0035] Figure 8 It is a schematic diagram of the position of the brain tissue in the slicing device of the present invention;

[0036] Figure 9 It is the front view of the brain tissue in the slicing device of the present invention;

[0037] Figure 10 It is a schematic diagram of the positioning of the slicing device of the present invention;

[0038] Figure 11Schematic diagram of the positioning angle of the slicing device of the present invention;

[0039] Figure 12 Schematic diagram of the positioning of the brain tissue of the present invention.

[0040] Figure 13 Front view of the positioning of the brain tissue of the present invention.

[0041] In the figure: 1. Slicing frame; 2. Bottom plate; 3. Positioning adjustment device; 4. Angle adjustment device; 5. Positioning rod; 6. Slide block; 7. Connection part; 8. Positioning block; 9. Angle adjustment rod; 10. Lifting adjustment rod; 11. Fixed plate; 12. Optic chiasm platform; 13. Visual plate; 14. Positioning needle; 15. Horizontal calibration line; 16. Angle positioning line; 17. Rotating shaft; 18. Slicing seam; 19. Brain tissue; 20. Sleeve; 21. Adapter tube; 22. Connecting rod; 23. Horizontal adjustment hole, 24. Guide hole. Specific embodiments

[0042] The following further describes the present invention in detail with reference to the accompanying drawings, which is an explanation rather than a limitation of the present invention.

[0043] Refer to Figure 1-13 , a standard cutting device for the ex vivo brain tissue of experimental mice, comprising a transparent slicing frame 1, a bottom plate 2, a positioning adjustment device 3 and an angle adjustment device 4.

[0044] The bottom plate 2 is arranged in the slicing frame 1. One end of the bottom plate 2 is rotatably connected to the slicing frame, and the other end of the bottom plate 2 is connected to the angle adjustment device 4. A visual chiasm platform 12 for positioning the brain tissue is arranged on the bottom plate 2. The positioning adjustment device 3 is arranged on the bottom plate and is located at the end far from the rotation of the bottom plate. An angle positioning line 16 is arranged on the side wall of the slicing frame 1. The projection of the center of the top surface of the visual chiasm platform on the side wall of the slicing frame coincides with the starting point of the angle positioning line 16. A vertical slicing seam 18 is also arranged on the side wall of the slicing frame 1, and the slicing seam 18 intersects with the angle positioning line.

[0045] The positioning adjustment device 3 includes a fixed plate 11, a positioning rod 5 and a bidirectional adjustment device. The bidirectional adjustment device is slidably connected to the fixed plate, and the positioning rod 5 is connected to the bidirectional adjustment device. The bidirectional adjustment device is used to adjust the axial position and height of the positioning rod 5. A positioning needle 14 is arranged at the end of the positioning rod. When the positioning needle 14 is located at the contact part of the left and right cerebral cortices of the brain tissue and the positioning needle is within the range of the angle positioning line, slicing the brain tissue along the slicing seam can obtain a coronal section of the brain tissue consistent with the standard brain atlas.

[0046] The angle adjustment device 4 includes a connection part 7 and an angle adjustment rod 9. The connection part 7 is arranged at the center of the end of the bottom plate and is located at one end away from the optic chiasm stage. The angle adjustment rod 9 is vertically installed on the rear end plate of the slicing frame. The lower end of the angle adjustment rod 9 is rotatably connected to the connection part, and the angle adjustment rod 9 can move up and down along the slicing frame to realize the adjustment of the angle of the bottom plate.

[0047] A clamping groove is arranged at the end of the connection part 7. Bar-shaped guide holes 24 are arranged on two side walls of the clamping groove. A connecting rod 22 is arranged in the guide holes. Both ends of the connecting rod 22 are located in the guide holes. A rotating connection pipe 21 is sleeved on the connecting rod 22. A threaded rod is arranged in the middle of the outer part of the rotating connection pipe 21. The threaded rod is connected to the angle adjustment rod 9 through a sleeve 20. A stepped hole is arranged inside the sleeve 20. The lower end of the angle adjustment rod 9 extends into the sleeve 20 and is connected to the sleeve through a nut. The end of the nut abuts against the stepped surface. The angle adjustment rod 9 is connected to the slicing frame through a thread. When the angle adjustment rod 9 is rotated, the connection part can be driven to move up and down through the connecting rod, and at the same time, the connecting rod 22 can move in the guide holes, so as to realize the rotation of the bottom plate.

[0048] The slicing frame 1 is made of transparent plexiglass, and both the top and the bottom are open. A rotating shaft 17 is arranged inside the slicing frame 1. The rotating shaft is arranged along the width direction of the slicing frame 1. The rotating shaft 17 is rotatably connected to the bottom plate, and the bottom plate can rotate along the rotating shaft 17. The optic chiasm stage is arranged at the width center of the bottom plate, and the axis of the optic chiasm stage is vertically intersected with the axial direction of the rotating shaft 17.

[0049] Horizontal calibration lines 15 are arranged on the side wall of the slicing frame. When the bottom plate is in a horizontal state, the horizontal calibration lines 15 coincide with the projection lines of the top surface of the bottom plate on the side wall of the slicing frame. The angle positioning lines are three lines, and their horizontal angles are 50°, 57° and 60° respectively. The optic chiasm stage is a cylinder arranged at the width center of the bottom plate. The center of the projection line formed by the projection of the top surface of the cylinder on the side wall of the slicing frame is the starting point of the angle positioning line. The angle positioning line starts from the center of the projection line and inclines towards the upper edge of the slicing frame 1 and the positioning adjustment device 3.

[0050] The slicing slit 18 is arranged on the side wall of the slicing frame, is perpendicular to the projection line of the optic chiasm stage on the side wall of the slicing frame and is located on the side of the projection line of the optic chiasm stage on the side wall of the slicing frame close to the positioning adjustment device. A cutting knife is inserted into the slicing slit 18 to cut the positioned brain tissue. There are three slicing slits 18, and the three slicing slits 18 are arranged at intervals and in parallel. The distances from the starting point of the angle positioning line are 3 mm, 6 mm and 10 mm respectively. The slicing slit 18 penetrates through the upper edge of the side wall of the slicing frame, and slicing slits are arranged on both side walls.

[0051] The two-way adjusting device includes a slider and a lifting adjusting rod 10. The fixing plate is vertically arranged on the bottom plate 2. A guiding groove is provided on the fixing plate. The slider is arranged in the guiding groove. The lifting adjusting rod 10 is rotationally connected to the fixing plate by threads. The lower end of the lifting adjusting rod 10 is located in the guiding groove and connected to the top of the slider 6. The upper end of the lifting adjusting rod 10 extends out of the top of the fixing plate. Rotating the lifting adjusting rod 10 can make the slider slide up and down along the guiding groove. The lower end of the lifting adjusting rod 10 is rotationally connected to a sleeve. The lower end of the sleeve is connected to the top surface of the slider by bolts. Its structure is the same as that of the angle adjusting rod and the connecting rod, and will not be elaborated here.

[0052] Chute grooves that cooperate with the guiding groove are provided on both sides of the slider. The chute grooves cooperate with the slide rails on the side walls of the guiding groove. The cross-section of the slide rail is triangular, and the chute groove is a concave triangle. It can also be designed as a cooperating T-shaped guide rail and T-shaped groove, or a dovetail groove and a cooperating dovetail guide rail.

[0053] A horizontal adjusting hole 23 is provided on the slider. A positioning rod is arranged in the horizontal adjusting hole. The positioning rod can move along the horizontal adjusting hole for adjusting the position of the positioning needle. A positioning block 8 is provided on one side of the slider. The end of the positioning rod passes through the positioning block 8 and extends out. A limit pin is provided on the positioning block 8 for limiting the horizontal position of the positioning rod.

[0054] The axis of the positioning rod and the axis of the bottom plate are in the same vertical plane. A positioning line is provided on the lower surface of the positioning rod. The positioning line is parallel to the axis of the positioning rod. The cross-section of the positioning rod is a symmetric triangle. The top surface of the positioning rod is a plane, and the bottom edge of the positioning rod is the positioning line.

[0055] The positioning needle is arranged at the end of the positioning rod. The tip of the positioning needle extends downward. Through the two-way adjusting device, the positioning needle can be located at the contact part of the left and right cerebral cortices of the brain tissue. In order to facilitate observing the position of the positioning needle, a visual plate 13 is provided on either side of the positioning needle close to the side wall of the slicing frame. The visual plate 13 and the positioning needle are in the same plane, and the lower end of the visual plate 13 is at the same height as the tip of the positioning needle. The position of the positioning needle can be obtained by observing the position of the lower end of the visual plate 13. Visual plates 13 are provided on both sides of the positioning needle. The upper ends of the visual plates 13 are fixedly connected to the end of the positioning rod by connecting arms. In this embodiment, the two visual plates and the positioning needle form an inverted mountain-shaped structure.

[0056] Embodiment 1

[0057] The manufacturing method of a standard cutting device for experimental mouse ex vivo brain tissue provided by the present invention will be described in detail below.

[0058] The manufacturing method of a standard cutting device for experimental mouse ex vivo brain tissue includes the following steps:

[0059] In this embodiment, according to the slicing position of the mouse brain, one end of the slicing frame is defined as the rostral end, and the other end is defined as the caudal end.

[0060] Step 1: Fabricate the slicing frame.

[0061] The slicing frame is made of transparent plexiglass into a rectangular frame structure, formed by bonding four pieces of transparent plexiglass. The internal dimensions of the rectangular frame are 50mm × 100mm.

[0062] Horizontal rotating shafts are provided at a distance of 30mm from the rostral end and a height of 22.5mm on the side wall of the slicing frame for connecting the bottom plate. Horizontal calibration lines are respectively provided at 25mm and 28mm above the bottom edge of the slicing frame.

[0063] An origin is set at a distance of 30mm from the rostral end of the slicing frame and 28mm above the bottom edge of the slicing frame as the starting point of the angle positioning line. Three angle positioning lines with angles of 50°, 57°, and 60° with the horizontal line are set with this starting point. The angle positioning lines slope towards the caudal end of the slicing frame and extend to the upper edge of the side wall of the slicing frame.

[0064] Three spaced and parallel slicing slits are provided on the side wall of the slicing frame. The slicing slits are set on the side closer to the caudal end of the origin and are respectively 3mm, 6mm, and 10mm away from the origin. The width of the slicing slit is 1mm, and the height is 35mm.

[0065] Step 2: Fabricate the bottom plate.

[0066] A transparent rectangular plexiglass with a length of 70mm × width of 40mm × thickness of 5mm is used as the bottom plate. A rotating shaft hole is provided at the thickness center of one end of the bottom plate. The bottom plate is connected to the rotating shaft through the rotating shaft hole. A connecting portion is provided at the caudal end of the bottom plate. At the same time, a lifting adjustment rod 10 is provided on the end plate at the caudal end of the slicing frame. The lifting adjustment rod 10 is rotatably connected to the connecting portion. The lifting adjustment rod is threadedly connected to the end plate. The angle of the bottom plate is adjusted by rotating the lifting adjustment rod.

[0067] An axial center line is marked along the width center of the surface of the bottom plate. At the same time, a transverse marking line of the axial center line is marked at a distance of 20mm from the rostral end of the bottom plate. The transverse marking line and the axis of the rotating shaft are located in the same vertical plane. An optic chiasm platform 12 is provided at the intersection of the axial center line and the transverse marking line of the bottom plate. The optic chiasm platform 12 is a cylinder with a diameter of 2mm and a height of 3mm.

[0068] Step 3: Fabricate the positioning and adjustment device.

[0069] Use a rectangular plexiglass with a height of 40 mm × width of 40 mm × thickness of 10 mm as the fixed plate. With the vertical center line as the reference, the lower part is hollowed out into a rectangular guide groove that is symmetrical left and right. The guide groove has a height of 30 mm × width of 22 mm. Slide rails are made on the side walls of the guide groove, and the fixed plate is bonded to the bottom plate.

[0070] Use a rectangular plexiglass with a height of 10 mm × width of 20 mm × thickness of 10 mm as the slider, and concave chutes are provided on both sides of the slider. The slider matches the ridge-shaped slide rail of the rear panel and can slide up and down on it; a triangular mortise is provided in the center of the slider, and the slider is connected to the fixed plate through a lifting adjustment rod 10. The lifting adjustment rod 10 is connected to the fixed plate through a thread.

[0071] Use transparent plexiglass to make a triangular pyramid slide rod with a length of 50 mm × bottom edge of 10 mm × height of 3 mm. The triangular pyramid can be inserted into the mortise of the slider to move back and forth. The bottom edge of the triangular pyramid shows the positive center line, and a positioning needle and a visual board 13 are bonded to the end of the positioning rod.

[0072] The following is a detailed description of the slicing method of an experimental mouse ex vivo brain standard cutting device provided by the present invention, including the following steps:

[0073] Standard positioning of ex vivo experimental brain tissue: To achieve the accurate matching of the brain coronal section with the standard brain atlas, it is necessary to correctly position it in space according to the morphological characteristics of the mouse brain, that is, to ensure that the section after the ex vivo brain is severed is consistent with the standard brain atlas at the dorsal-ventral, rostral-caudal, and left-right axis levels.

[0074] Step 1: Place the ex vivo brain tissue longitudinally on the bottom plate, and place the optic chiasm of the brain tissue on the optic chiasm platform of the bottom plate.

[0075] Step 2: Adjust the position of the brain tissue so that the midline of the ventral surface of the brain tissue in the rostral-caudal direction coincides with the axial center line of the bottom plate.

[0076] Adjust the height of the slider and move the positioning rod so that the positioning rod is located at the top of the brain tissue. Adjust the ventral position of the brain tissue so that the sagittal suture of the brain tissue coincides with the positioning line of the positioning rod.

[0077] After adjusting the brain tissue, the ventral midline of the brain tissue coincides with the axial center line of the bottom plate, and at the same time, the sagittal suture on the back of the brain tissue also coincides with the positioning line of the positioning rod.

[0078] Step 3: Adjust the position of the positioning needle so that the tip A of the positioning needle touches the contact part of the left and right cerebral cortices of the ex vivo brain at the sagittal suture, that is, the confluence part of the left and right cerebral cortices.

[0079] Step 4: Adjust the angle of the base plate through the angle adjustment device 4 so that the tip of the positioning needle is within the range of the angle positioning line, that is, the projection of the lower end B of the visual plate at the section frame falls within the range of the angle positioning line.

[0080] For rat brain tissue, the tip B of the positioning needle is within the range between the two angle positioning lines of 50° and 60°; for mouse brain, the tip B of the positioning needle is within the range between the two angle positioning lines of 57° and 60°.

[0081] Step 5: Insert a blade into the section slit, and move the blade along the section slit to cut the brain tissue.

[0082] Segmented cutting of the excised brain of the experimental animal: To ensure good sectioning effect and obtain a standard brain coronal section, it is necessary to section the intact excised large / small mouse brain. After sectioning, move the brain block to the freezing table for freezing. The placement operation of freezing the brain block is the same as that of the conventional sectioning operation, that is, tightly and flatly adhere the cut end of the brain block to the freezing table. The operation steps are as follows.

[0083] Step 6: After the above positioning of the brain tissue, according to the need, the intact brain tissue can be sectioned by vertically cutting along the cutting slit on the outer side plate of the sectioning blade.

[0084] Step 7: Use a microtome to trim the embedding medium that has been frozen on the freezing table.

[0085] Step 8: Press the sectioned surface of the excised brain tissue block tightly against the trimmed embedding medium on the freezing table, and then use a microtome to section, and a brain coronal section matching the standard brain atlas can be obtained.

[0086] A standard cutting device for the excised brain of an experimental animal provided by the present invention is applicable to all researches in the field of brain research that require observing, analyzing, and calculating experimental results and data by comparing with a standard brain atlas on a coronal section. After positioning and cutting the excised brain by this method, and then through conventional frozen sectioning, a brain coronal section matching the standard brain atlas can be obtained, making the data analysis of related researches more accurate.

[0087] The above content is only to illustrate the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A standard cutting device for the isolated brain tissue of experimental mice, characterized in that, It includes a transparent section box (1), a bottom plate (2), a positioning and adjusting device (3) and an angle adjusting device (4); The bottom plate (2) is arranged in the section box (1). One end of the bottom plate (2) is rotatably connected to the section box, and the other end of the bottom plate (2) is connected to the angle adjusting device (4). A chiasma platform (12) for positioning the brain tissue is arranged on the bottom plate (2). The positioning and adjusting device (3) is arranged on the bottom plate and is located at the end far from the rotation of the bottom plate. Angle positioning lines (16) are arranged on the side wall of the section box (1). The intersection of the projection of the center of the top surface of the chiasma platform on the side wall of the section box and the angle positioning line (16) coincides. A vertical section slit (18) is also arranged on the side wall of the section box (1), and the section slit (18) intersects with the angle positioning line; The positioning and adjusting device (3) includes a fixing plate (11), a positioning rod (5) and a bidirectional adjusting device. The bidirectional adjusting device is slidably connected to the fixing plate, the positioning rod (5) is connected to the bidirectional adjusting device, and the bidirectional adjusting device is used to adjust the axial position and height of the positioning rod (5). A positioning needle (14) is arranged at the end of the positioning rod. When the positioning needle (14) is located at the contact part of the left and right cerebral cortices of the brain tissue and the positioning needle is within the range of the angle positioning line, sectioning the brain tissue along the section slit can obtain a coronal section of the brain tissue.

2. The standard cutting device for the isolated brain tissue of experimental mice according to claim 1, wherein The angle adjusting device (4) includes a connecting part (7) and an angle adjusting rod (9). The connecting part (7) is arranged at the end of the bottom plate and is located at the end far from the chiasma platform. The angle adjusting rod (9) is vertically installed on the rear end plate of the section box. The lower end of the angle adjusting rod (9) is rotatably connected to the connecting part, and the angle adjusting rod (9) can move up and down along the section box.

3. The standard cutting device for the isolated brain tissue of experimental mice according to claim 1, characterized in that, A clamping groove is arranged at the end of the connecting part (7). Strip-shaped guide holes (24) are arranged on the two side walls of the clamping groove, and a connecting rod (22) is arranged in the guide holes. The lower end of the angle adjusting rod (9) is rotatably connected to the connecting rod.

4. An experimental mouse ex vivo brain tissue standard cutting device according to claim 1, characterized in that, A rotating shaft (17) is arranged in the section box (1). The chiasma platform is arranged at the width center of the bottom plate, and the axis of the chiasma platform is vertically and intersectingly arranged with the axial direction of the rotating shaft (17).

5. An experimental mouse ex vivo brain tissue standard cutting device according to claim 1, characterized in that, Horizontal calibration lines (15) are arranged on the side wall of the section box for calibrating the horizontal state of the bottom.

6. The standard cutting device for the isolated brain tissue of experimental mice according to claim 1, wherein The angle positioning lines are three lines, and their horizontal angles are 50°, 57° and 60° respectively.

7. The standard cutting device for the isolated brain tissue of experimental mice according to claim 1, characterized in that, The bidirectional adjusting device includes a lifting and adjusting rod (10) and a slider (6); The fixing plate is vertically arranged on the bottom plate (2). A guide groove is arranged on the fixing plate. The slider is arranged in the guide groove. The lifting and adjusting rod (10) is rotationally connected to the fixing plate through a thread. The lower end of the lifting and adjusting rod (10) is located in the guide groove and is rotationally connected to the top of the slider (6). The upper end of the lifting and adjusting rod (10) extends out of the top of the fixing plate. Rotating the lifting and adjusting rod (10) can make the slider slide up and down along the guide groove.

8. An experimental mouse ex vivo brain tissue standard cutting device according to claim 7, characterized in that, A horizontal adjustment hole (23) is provided on the slider, the positioning rod is arranged in the horizontal adjustment hole, the positioning rod can move along the horizontal adjustment hole, a positioning block (8) is arranged on one side of the slider, the end of the positioning rod passes through the positioning block (8) and extends out, and a limit pin is arranged on the positioning block (8) for limiting the horizontal position of the positioning rod.

9. An experimental mouse ex vivo brain tissue standard cutting device according to claim 1, characterized in that, A visual plate (13) is further arranged at the end of the positioning rod and is in the same plane as the positioning needle, and the visual plate (13) is close to the inner side wall of the cutting frame.

10. A cutting method of the cutting device for the standard cutting of the in vitro brain tissue of experimental mice according to any one of claims 1-9, characterized in that, It includes the following steps: Step 1: Place the excised brain tissue on the bottom plate in a horizontal state, and place the optic chiasm of the brain tissue on the optic chiasm platform of the bottom plate; Step 2: Adjust the position of the brain tissue so that the midline in the rostrocaudal direction of the ventral surface of the brain tissue coincides with the axial center line of the bottom plate, and at the same time make the sagittal suture on the back of the brain tissue coincide with the axis of the positioning rod; Step 3: Adjust the position of the positioning needle so that the tip of the positioning needle touches the contact part of the left and right cerebral cortices of the brain tissue; Step 4: Adjust the angle of the bottom plate so that the tip of the positioning needle is within the range of the angle positioning line; Step 5: Insert a blade into the sectioning slot, and the blade moves downward along the sectioning slot to cut the brain tissue.

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