【Animal Modeling】-Establishment and behavioral evaluation of tree shrew spinal cord injury model
动物造模,脊髓半横断损伤模型
z-bo
2022-06-05
491
1. The purpose of the experiment
Establish a wooden juvenile spinal cord hemilateral injury model and an evaluation method for hind limb motor dysfunction.
2. Experimental principle
The sharp weapon cut destroyed half of the spinal cord.
3. Experimental materials and methods
(1) Experimental materials
1. The required equipment is a fully automatic sterilizer. Electric heating type constant temperature blast drying oven.
2. Necessary reagents hydrate chloral hydrate powder, 0.9% sodium chloride solution, medical iodine disinfectant.
3. Reagents for preparing 3.6% chloral hydrate solution: Weigh 3.6 g of chloral hydrate powder, dissolve it in 100 ml of sterile 0.9% sodium chloride solution and mix well. Store at room temperature.
4. Experimental animal female juvenile, weighing (110±10) g. (2) Experimental methods and operating steps 1. Preparation of hSCI model (1) Anesthesia: Anesthesia was performed by intraperitoneal injection of 3.6% chloral hydrate (1 mL/100 g).
(2) Skin preparation: After the anesthesia is completed, use an electric razor to shave the chest and back, and paste the limbs on a square wooden board.
(3) Towel disinfection: regularly disinfect the chest and back skin with medical iodine disinfectant. Place sterile hall towels.
(4) The position of the spine segments: 7 cervical vertebrae, 13 thoracic vertebrae, 6 lumbar vertebrae, and 6 spinous processes of lumbar vertebrae clearly projected backward. Use it to mark the T10 spinous process of your head. suddenly. Or count from the 13th rib to the 10th rib, and the corresponding spinous process is the T10 spinous process.
(5) Publish T10 spinal segment: T9-T10 connective spinous process (count from the 13th rib to the 10th rib, the corresponding spinous process is T10 spinous process), and make a 2cm skin incision used to bluntly separate both sides Of the spinal muscles to expose the T9–T10 spinous processes and lamina. Clamp the T8 spinous process with forceps. The sharp temporal bone bites the T9-T10 spinous process and lamina. Be careful not to damage the dura mater of the T10 spinal cord.
(6) T10 spinal cord transection: Use a sharp knife to pierce the spinal cord along the dorsal groove of the spinal cord, pull it to the left until it reaches the front wall of the spinal canal, cut off the left half of the spinal cord at T10, and then swab the ball to stop bleeding.
(7) Closing the incision: Suture the deep fascia and skin in turn to close the incision.
(8) Post-operative care: 200,000 U/0.2 ml penicillin was injected intraperitoneally after the operation, once a day for 3 consecutive days to prevent infection. Manual urine squeezing care will be performed every morning and evening. They are housed in individual cages, watered and fed regularly, and maintained with natural light and ventilation.
2. After the left half of the T10 spinal cord is injured 1d, 3d, 5d, 7d, 9d, 11d, 13d, 15d, the behavioral evaluation uses the BBB motor function assessment scale (Table 12-1, 21 levels in total). Do it. We evaluated the motor dysfunction of the left lower limb. When scoring, place the animal on a platform that is wide enough and barrier-free, and observe the hindlimb gait and physical activity for 5 minutes.
(3) Precautions for experimental operation
(1) Wooden juveniles are harder than mice. The process of biting the spinous process and lamina requires special care to expose the spinal cord to prevent dural damage. spinal cord.
(2) Wood shavings are small in size, thin in skin, and weak in resistance after injury. After surgery, put a layer of sawdust at the bottom of the breeding cage to keep warm and prevent pressure sores.
IV. Experimental results
(1) On the first day after TJJ left hemisection, the BBB score of the motor function of the right lower limb was (2.90±4.30) points, n = 5; 15 days after the injury, the BBB score was (12.80±2.00) points, n = 5 ,
(2) 26.32% of the right leg was bitten (n = 19).
5. Result analysis
(1) This method can effectively prepare a semi-anatomical model of the rape T10 spinal cord.
(2) After a unilateral amputation injury in which the tree compresses the T10 spinal cord, he may self-mutilate and bite the lower limb due to hyperalgesia in the lower limbs.
6. Experience and experience
(1) Wood prawns are small and thin. It is especially important to keep warm after injury to prevent pressure sores. Appropriate measures can effectively reduce postoperative animal mortality.
(2) After juvenile spinal cord injury, keep ventilation and heat in the breeding room, keep the indoor humidity constant (40% to 60%), squeeze urine in time, and keep the cage clean. , Can effectively improve the survival rate of animals.
