实验动物给药 z-bo 2020-10-13 372

　　(1) Subcutaneous injection

　　When injecting, lift the skin with the left thumb and index finger, and pierce the syringe under the skin with a 5 (1/2) gauge needle. The subcutaneous injection site is used for guinea pigs on the back of the thigh or inside the lower abdomen, rats in the lower abdomen, and rabbits on the back or groin.

　　(2) Intradermal injection

　　For intradermal injection, it is necessary to remove the fur at the injection site. After disinfection, use the left thumb and index finger to compress the skin. Use tuberculosis between the fingers. An infusion syringe with four (1/2) fine needles adheres to the skin surface and penetrates, then lifts and pierces a little to inject liquid. At this time, small white bumps can be seen on the skin surface.

　　(3) intramuscular injection

　　Intramuscular injection must be the part where the muscles are strong and the large blood vessels cannot pass. Usually, choose the waist. The injection allows the muscle to penetrate quickly and vertically. If the blood does not return, the needle can be injected. For intramuscular injection of small animals (such as mice and rats), please use your left hand to grasp the skin of the mouse’s ear and head, and place the needle on the outer thigh muscle with a 5 (1/2) needle syringe in your right hand in. Puncture injection of liquid medicine.

　　(4) Intraperitoneal injection

　　When testing large and small white mice, hold the animal with the left hand and point the abdomen upward, and then use the right hand to insert the injection needle into the left (or right) lower abdomen under the skin. , Push the needle forward 0.5-1.0 cm, pass the abdominal muscle at a 450 degree angle, fix the needle, and then slowly inject the liquid medicine. To prevent damage to the internal organs, place the animal's head down, and then move the internal organs to the abdomen. If the experimental animal is a rabbit, the needle insertion site is 1 cm away from the white line in the lower abdomen.

　　(5) intravenous injection

　　1. The blood vessels in rabbit ears are clearly distributed. The center of the rabbit ear is the artery, and the outer edge of the ear is the vein. The internal vein is deep and difficult to fix, so it is not used. The external vein is very shallow, easy to fix, and is often used. First pull out the coat at the injection site, flick or rub the rabbit’s ear with your fingers to fill the vein, pinch the proximal end of the vein between the index finger and middle finger of your left hand, tighten the distal end of the vein with your thumb and ring finger, wrap it with your right hand Fingers and little fingers hold the syringe with a 6-gauge needle, pierce the needle as far as possible from the distal end of the vein, move the thumb of the needle to fix the needle, loosen the index finger and middle finger, then inject the liquid, then pull out the needle and hold the eye for a while.

　　2. Mice and rats usually use tail vein injection. There are three tail veins, one on the left, right and back. The left and right tail veins are easy to fix. You can use one on the back, but fixing the position is not easy. During the operation, the animal was fixed on the rat's barrel or tightened with a beaker to expose the tail. Soak the tail in warm water at 45-50°C for 30 minutes, or wipe it with ethanol to expand blood vessels and soften the epidermis. Use your index finger to pinch both sides of the rat’s tail to fill the veins, lift the tail from below with your middle finger, clamp the end of the tail with your ring finger and little finger, hold the syringe with your right hand, 4 (1/2)) connect the fine needle to make the needle Parallel to the vein (less than 300), insert the needle 1/4 below the tail (2 to 3 cm from the tip of the tail) where the skin is thin and easy to penetrate. First, slowly inject a small amount of drug solution. If there is no resistance, the needle can enter the vein and continue. injection. After injection, bend the tail to the injection side to stop bleeding. If you need to repeat the injection, start as much as possible, and then move the injection to the bottom of the tail.

　　(6) Oral administration

　　In acute studies, oral administration is mainly used for forced feeding. The method is accurate dosage, applicable to mice, rats, rabbits and other animals. For mice, rats (or guinea pigs), use a blood transfusion needle or a thin waist needle to flatten the tip of the bevel, and weld a round tip around the tip of the needle. Be careful not to block the pinhole. This is a forced breeding needle. Use round head hard glass capillary tube or special plastic capillary tube to launch tube. For forced feeding, push the needle of the syringe to inhale the liquid. Place the animal’s skin on the back and neck of the mouse with the left hand, hold the syringe with the right hand, insert the needle for forced feeding into the animal’s mouth, and then slowly insert the esophagus along the back wall of the pharynx. The animal should be fixed in a vertical position and there should be no resistance when inserting the needle. If you feel resistance or the animal suffers, you should stop or pull the needle immediately to avoid damage or puncture of the esophagus and accidental intrusion into the trachea. Generally, a 3-4cm forced oral needle can be inserted into mice, and a 4-6cm strong oral needle can be inserted into rats and guinea pigs before injection. The commonly used mandatory doses are: 0.2-1 ml for mice, 1-4 ml for rats, and 1-5 ml for guinea pigs.

　　(7) Other management methods

　　1. Drugs or toxic gases used for respiratory tract management in the form of dust, gas or mist should be managed through the respiratory tract of animals. For example, in a general experiment, ether is used to inhale animal anesthetics, a certain amount of ammonia, carbon dioxide, etc., to observe changes in breathing and circulation, regular amounts of sulfur dioxide, wood shavings smoke, etc. Inhalation can cause animal models such as chronic bronchitis. It is used more widely, especially in toxicology experiments.

　　2. Transdermal administration is required for skin administration to identify the absorption of drugs or toxins through the skin, local effects, sensitization and photosensitivity. For example, rabbits and guinea pigs often use specific areas on the back of the skin to remove hair and apply specific liquids to the skin, which are usually absorbed by the skin.

　　3. This method is mainly used for spinal anesthesia or cerebrospinal fluid extraction.

　　Domestic spinal canal injection: Put the rabbit in a natural position, bend the tail, cut off the posterior hair around the seventh lumbar vertebrae with coarse scissors, disinfect with 3% iodine colorant, use after drying, wipe off the iodine with 79% ethanol. Touch the seventh lumbar space (between the seventh lumbar vertebra and the first vertebra) just below the midpoint of the connecting line of the rabbit's posterior vertebrae, and then insert a lumbar needle. When the needle reaches the spinal canal (subarachnoid space), you will see the rabbit's hind limbs beating. This indicates that the puncture needle has entered the spinal canal. Do not pierce at this time to avoid damage to the spinal cord. After fixing the needle, inject the medicine.

　　Four. The brain Sisterna Magna is administered under animal anesthesia.

　　Fives. This method of intracerebral administration is often used in animal experiments with microchemicals. Inoculate pathogens into the brains of animals for inspection and observe various changes after inoculation. When administering medicine to the rat’s brain, please choose a 5 (1/2) needle. The end of the needle-tip plastic tube must be 2 mm deep. Puncture the brain from the center of the rat’s forehead, and then apply the medicine or inoculum. injection. When performing intracerebral injections into guinea pigs, rabbits, etc., it is necessary to use an intracranial steel needle to penetrate the skull, then use the injection needle to penetrate the brain, and then slowly inject the test object. Have. The infusion rate should be slowed down to avoid a sharp rise in intracranial pressure.

　　6. This method of administration is usually used to anesthetize animals. For intrarectal administration in rabbits, please use a rubber tube for edema or use the 14th urinary catheter. Apply petroleum jelly to the rubber tube or catheter head, the assistant squats on the table, gently press the rabbit's head and forefoot with the left arm and left flanks, and hold the rabbit's tail with the left hand to expose the anus and right hand. Using lightly holding the hind limbs, the experimenter inserted the rubber tube into the rabbit's anus to a depth of 7-9 cm. For female animals, please be careful not to accidentally insert them into the vagina (the anus is near the bottom of the tail). After inserting the rubber tube, insert the syringe and the rubber tube firmly to inject the liquid medicine.

　　7. This method of intra-articular administration is commonly used to replicate animal models of arthritis. When using a rabbit, fix the rabbit's lying position on the rabbit fixation table, cut off the joint skin, disinfect with iodine or ethanol, and then fix the joint by hand from below and on both sides, and place the skin slightly on one side. I will move it. Insert the needle about 0.5 cm above the ligament junction. Insert the needle diagonally from the upper front to the lower back until the resistance of the needle decreases, then retract the needle and push it vertically into the joint cavity. When the needle enters the joint cavity, it usually feels like a hole in the membrane, indicating that the needle can enter the knee joint cavity and inject liquid medicine.