动物造模,扩张型心肌病变模型 z-bio 2023-11-02 835

　　1. Six adult hybrid dogs weighing (17.04 ± 2.03) kg were used as experimental animals.

　　2. Experimental method: Sodium pentobarbital was prepared into a 3% concentration and injected intraperitoneally at 1mg/kg. After anesthesia, echocardiography was performed to measure the left ventricular diameter, left ventricular posterior wall, and interventricular septal thickness. Properly replenish fluids during the experiment. Preparation of a canine model of third degree atrioventricular block using Hip's procedure for ablation. Then, a small incision was made on the right side of the dog's neck to separate and expose the external jugular vein. After successful puncture using the Sedinger method, the guide wire, vascular sheath, and permanent pacing electrode were sequentially inserted. The fixed end of the electrode head is fixed at the canine right ventricular apex, and the electrode outlet end is sutured and fixed subcutaneously. The pacemaker is set to VOO mode, with a fixed frequency of 250 beats per minute, an output voltage of 5.0V, and a pulse width of 0.5 milliseconds. The electrocardiogram confirms good pacing, sutures each incision, removes the sheath from the right femoral vein to stop bleeding, and injects 20mg of furosemide intravenously before awakening from anesthesia to diuresis. After the surgery, all dog models were kept for 3 weeks, and B-ultrasound examinations were repeated. Relevant parameters were measured for self control before and after the surgery. Then the dog was euthanized, and the heart was weighed as a model group. The maximum left ventricular diameter and maximum ventricular wall thickness were measured, and the specimens were stained with pathological sections (HE). Another group of 8 normal adult hybrid dogs served as a control group.

　　3. Reference results Experimental results: The model group was larger than the control group in terms of body weight, total heart weight, maximum left ventricular diameter, and maximum wall thickness. Cardiac ultrasound examination: Comparison before and after the model: Left ventricular cavity enlargement, thinning of left ventricular posterior wall and interventricular septum. Pathological section: The myocardial cells in the model group showed swelling and varying sizes, with vacuoles appearing in the cytoplasm and an increase in the perinuclear space.