动物造模,药效评价,体内血栓 z-bio 2024-07-29 1262

　　1. Modeling material animals: Wistar rats, male or female, weighing 200-250g; Medications: Ethyl carbamate, heparin injection; Equipment: Disposable intravenous catheter, BL-420 biological function experimental system.

　　2. The modeling method divides the rats into two groups. One group is the physiological saline model group, and the other group is the heparin model group. Both groups of animals were anesthetized with 3% ethyl carbamate (5ml/kg), and tracheal intubation was performed. The right common carotid artery was separated, and arterial catheterization was performed using a venous catheter. The catheter was connected to the BL-420 system through a pressure transducer, and the blood pressure curve was recorded. The physiological saline model group was injected with physiological saline through the femoral vein, while the heparin model group was injected with heparin (1200U/kg). 5 minutes after administration, a self-made hook shaped protective electrode was placed 0.5cm below the arterial catheter (near the heart) to contact the common carotid artery. The artery was moderately raised to block blood flow, causing the blood pressure curve to disappear and become a straight line. Activate the stimulator and continuously stimulate the arteries with direct current. Assuming a stimulation intensity of 3mA, a stimulation frequency of 10Hz, a wave width of 5.0ms, and a delay of 0.1ms. Observe the changes in arterial color at the stimulated area during the stimulation process. After the color turns purple, relax the electrode every 20 seconds, but the electrode is still in contact with the artery. Observe whether there is a pressure curve. If a pressure curve appears, it indicates that the thrombus has not completely blocked the artery, and continue to stimulate; If no pressure curve appears, stop the stimulation and record the time from the start of stimulation to the disappearance of the pressure curve, which is the time of thrombus blockage.

　　3. Modeling principle: Damage to endothelial cells can lead to thrombosis.

　　4. Changes after modeling: Both model groups showed arterial embolism. The average thrombus blockage time in the saline model group was (15.6 ± 5.3) minutes, while the average thrombus blockage time in the heparin model group was (90.2 ± 12.5) minutes.

　　5. Precautions: During the process of stimulating the common carotid artery, electrodes should be used to lift the artery moderately to flatten it and block blood flow, in order to prevent newly formed thrombi from being scattered by blood flow and avoid complete blockage.