Method for chronic continuous administration in ventricle of experimental animal

Abstract

The invention discloses a chronic continuous drug delivery method in the ventricle of an experimental animal, and belongs to the technical field of animal model construction. The method comprises the following steps: (1) anesthetizing an animal; (2) longitudinally cutting the skin of the parietal bone along the direction of the occipital bone macropore formed by the midpoint of the connecting line of the two eyes; (3) disinfecting the head and removing connective tissues on the surface of the parietal bone; (4) penetrating through the left ventricle by using a brain stereotaxic instrument; (5) simultaneously connecting a chronic drug delivery pump with a catheter, soaking the chronic drug delivery pump in normal saline for 20-28 hours, taking out the chronic drug delivery pump, filling the chronic drug delivery pump with a tested drug, and injecting the tested drug into the catheter; (6) cutting the catheter to a proper length, inserting the far end of the catheter into the left ventricle, fixing, and after the catheter is dried up, remaining the chronic drug delivery pump under the skin of the head along the opening of the skin of the head; and (7) sewing a head opening. According to the method, insufficient drug effect persistence caused by too high drug metabolism speed can be avoided, and in addition, injury to the tested animal due to multiple times of opening and puncturing can be reduced, so that non-drug influence is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of animal model construction, and in particular relates to a method for chronic continuous drug administration within the cerebral ventricle of experimental animals. Background Art

[0002] In many drug trials, drugs for the central nervous system need to be injected into the relevant areas of the brain. However, many drugs cannot pass through the blood-brain barrier and enter the brain to exert their effects. Although many researchers use brain injections to inject drugs directly into the brain to exert their effects, due to the brain's metabolic problems, there will be errors in the judgment of the effective dose, which often causes the effective dose of the drug to be inconsistent with the physiological capacity, resulting in drug waste and experimental errors. Summary of the invention

[0003] One of the purposes of the present invention is to provide a method for chronic continuous drug administration into the cerebroventricular cavity of an experimental animal, the method comprising the following steps:

[0004] (1) Anesthetize the animal;

[0005] (2) Cut the parietal skin longitudinally along the midpoint of the line between the two eyes to the foramen magnum;

[0006] (3) Disinfect the head and remove the connective tissue on the surface of the parietal bone;

[0007] (4) Use a stereotaxic apparatus to penetrate the left ventricle;

[0008] (5) At the same time, connect the chronic drug administration pump to the catheter and soak it in normal saline for 20-28 hours. After taking it out, load it with the test drug and inject the test drug into the catheter;

[0009] (6) Cut the catheter to an appropriate length, insert the distal end of the catheter into the left ventricle and fix it, and place the chronic drug delivery pump under the skin of the head through the opening of the skin;

[0010] (7) Suture the head opening.

[0011] Preferably, the animal in step (1) is a mouse.

[0012] More preferably, sodium pentobarbital is used for anesthesia in step (1).

[0013] More preferably, the coordinates of the brain stereotaxic instrument in step (4) are 3 mm to the left, 1 mm to the back, and 1.5 mm in depth from the bregma.

[0014] More preferably, in step (5), after the chronic drug administration pump is connected to the catheter, it is soaked in physiological saline for 24 hours.

[0015] More preferably, the amount of the test drug loaded in the chronic drug delivery pump in step (5) is 50 - 80 μL.

[0016] More preferably, the weight of the chronic drug delivery pump is recorded after loading the test drug in step (5).

[0017] More preferably, in step (6), the distal end of the catheter is inserted into the left cerebral ventricle and fixed with bone cement.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The method of chronic continuous drug delivery into the cerebral ventricle provided by the present invention can avoid the insufficient persistence of drug efficacy caused by the too fast drug metabolism rate. In addition, it can reduce the harm brought to the test animals by multiple openings and punctures, thereby reducing non-drug effects. Description of the Drawings

[0020] Figure 1 It is the process of drilling holes in the mouse brain in Example 1. Detailed Embodiments

[0021] Example 1

[0022] This example provides a method for chronic continuous drug delivery into the cerebral ventricle of experimental animals, and the specific steps are as follows:

[0023] 1. Anesthetize the mouse: sodium pentobarbital (30 mg / kg);

[0024] 2. Longitudinally incise the parietal bone skin along the midpoint of the line connecting the two eyes towards the foramen magnum;

[0025] 3. Wipe the parietal bone with hydrogen peroxide to remove the connective tissue on the surface of the parietal bone;

[0026] 4. Use a stereotaxic apparatus to penetrate into the left cerebral ventricle, coordinates: 3 mm to the left of the anterior fontanelle, 1 mm backward, depth 1.5 mm (see Figure 1 );

[0027] 5. Connect the catheter to the chronic drug delivery pump (RWD implanted sustained-release pump, specification 100 μL, model 1004W) in advance, soak it in physiological saline for 24 h, take it out, load 50 - 80 μL of the test drug (it can be any drug for intraventricular administration, and in principle, drugs that are not easily permeable through the blood-brain barrier are more suitable for this method), record the weight after loading the drug, and inject the test drug (without air bubbles) into the catheter;

[0028] 6. Cut the catheter to an appropriate length, insert the distal end of the catheter into the left cerebral ventricle, and fix it with bone cement. After it dries, leave the chronic drug delivery pump under the head skin through the opening in the head skin;

[0029] 7. Suture the head opening;

[0030] 8. Closely observe the animal's condition and the skin healing situation after the operation, with special emphasis on observing the skin of the head to ensure no necrosis.

[0031] 9. Verification method:

[0032] 1) Remove the chronic drug delivery pump at the end of the experiment and record the weight.

[0033] 2) Detect the drug or related products in the cerebrospinal fluid.

[0034] 3) Detect the drug or related products in the brain tissue or spinal cord.

[0035] The embodiments described above are only for describing the preferred mode of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for chronic continuous drug administration into the cerebroventricular cavity of an experimental animal, characterized in that: The method comprises the following steps: (1) Anesthetize the animal; (2) Cut the parietal skin longitudinally along the midpoint of the line between the two eyes to the foramen magnum; (3) Disinfect the head and remove the connective tissue on the surface of the parietal bone; (4) Use a stereotaxic apparatus to penetrate the left ventricle; (5) At the same time, connect the chronic drug administration pump to the catheter and soak it in normal saline for 20-28 hours. After taking it out, load it with the test drug and inject the test drug into the catheter; (6) Cut the catheter to an appropriate length, insert the distal end of the catheter into the left ventricle and fix it, and place the chronic drug delivery pump under the skin of the head through the opening of the skin; (7) Suture the head opening.

2. The method according to claim 1, characterized in that: The animal in step (1) is a mouse.

3. The method according to claim 2, characterized in that In the step (1), sodium pentobarbital is used for anesthesia.

4. The method according to claim 3, characterized in that The coordinates of the brain stereotaxic instrument in step (4) are 3 mm to the left, 1 mm to the back, and 1.5 mm in depth from the bregma.

5. The method according to claim 4, characterized in that In the step (5), after the chronic drug administration pump is connected to the catheter, it is soaked in physiological saline for 24 hours.

6. The method according to claim 5, characterized in that In step (5), the amount of the test drug loaded into the chronic dosing pump is 50-80 μL.

7. The method according to claim 6, characterized in that In the step (5), the weight of the chronic dosing pump is recorded after the test drug is loaded.

8. The method according to claim 7, characterized in that In step (6), the distal end of the catheter is inserted into the left ventricle and fixed with bone cement.

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