动物造模,自体血栓大脑中动脉闭塞模型 z-bio 2023-10-09 2046

　　1. Animal modeling materials: Wistar rats, with half male and half female, weighing 250-350g; Medication: 6% chloral hydrate, thrombin, sodium citrate (0.109mol/L); Instruments: Physiological multi-channel instrument, epidural catheter, 22G intravenous indwelling needle.

　　2. Modeling method

　　(1) Extraction of arterial blood: Animals were anesthetized by intraperitoneal injection of a 6% chloral hydrate solution of 35mg/100g body weight. The right common carotid artery (CCA) and internal carotid artery (ICA) were separated using conventional methods through a median incision in the neck, and the pterygopalatine artery was isolated and ligated. Free the distal end of the external carotid artery (ECA) and ligate it, coagulate its branches, clamp CCA and ICA with microvascular clamps, cut the ECA near the ligation line, insert a 22G indwelling needle, open the microvascular clamp at CCA, extract 0.5ml of arterial blood, ligate the proximal end of ECA at 1mm from the bifurcation of the carotid artery, inject a small amount of heparin saline into the distal end, and open the vascular clamp.

　　(2) Preparation of improved thrombus: Immediately inject 0.5ml of arterial blood containing 0.75 μ Mix sodium citrate (0.109mol/L) in an EP tube and centrifuge at 5000r/min for 1 minute. Take poor platelet plasma 160 μ l. RBC10 μ L and 1 unit of thrombin (250000 units/L), 30 μ Mix a solution of calcium chloride (0.5mol/L) and immediately inhale it into a plastic tube with an inner diameter of 0.58 or 0.65mm. After 2 minutes, transfer the thrombus to phosphate buffer to obtain a light red thrombus with a diameter of 0.35mm or 0.45mm. Under a surgical microscope, cut it into small sections about 2mm in length, and inhale 6 thrombi in sequence into a PE50 tube, with an interval of 2-3cm between the thrombi, for later use.

　　(3) Thrombosis injection: After the thrombus is prepared, the model group anesthetizes the animal again, exposes the cervical artery, clamps the CCA and ICA, and then unlocks or cuts the silk thread near the heart end of the ECA. The indwelling needle is inserted and fixed again at the ECA incision, and after removing the needle core, the ICA vascular clamp is opened to see the blood flowing back from the ICA. After the gas inside the indwelling needle is completely discharged, a PE50 tube is connected, and the other end is connected to a syringe with 0.25ml phosphate buffer solution, Inject thrombus sequentially (about 30 seconds), ligate ECA, open blood vessel clamp at CCA, and suture the incision. The operation process of the sham surgery group was the same as that of the model group, but only 0.2ml of buffer was injected.

　　3. The principle of modeling is to establish a middle cerebral artery occlusion model using autologous thrombus in rats.

　　4. Changes after modeling: MRI results showed abnormal signals of DWI in all modeling animals 15 minutes after MCAO, gradually expanding from the tail, lateral putamen, and parietal cortex. Lactic acid signals were observed in corresponding areas on H-MRS, and the lactate peak gradually deepened.

　　Neurological deficit score: model group