动物造模,药效评价,心力衰竭 z-bio 2024-08-15 384

　　1. Modeling material animal: Healthy aged Northwest hybrid dog, male, with an average age of (8.6 ± 0.7) years and an average weight of (18.6 ± 2.5) kg; Medications: pentobarbital, heparin, penicillin, formaldehyde (40g/L), 76% acetic acid iodobenzoic acid, 10% potassium chloride injection, ethylenediaminetetraacetic acid, etc; Instrument: V00 pacemaker (frequency 240 beats/min, output voltage 5.0V, pulse width 0.5ms).

　　2. The modeling method involves observing and recording the general condition of the dog, followed by intraperitoneal anesthesia with 3% pentobarbital 30mg/kg. After successful anesthesia, the precordial and bilateral inguinal areas are prepared and placed on a catheterization bed for endotracheal intubation, limb fixation, and electrocardiogram monitoring. Ultrasonic measurement of LVDD; Innocor measures cardiac output and records heart rate (HR); Femoral vein puncture was performed to extract 2ml of venous blood, which was anticoagulated with EDTA. The concentration changes of vascular endothelin-1 were detected by radioimmunoassay. A sheath tube was inserted and connected to the Swam Ganz catheter for measurement and recording of right atrial pressure and pulmonary capillary wedge pressure at the electrophysiological research workstation; Femoral artery puncture was performed to measure the mean arterial pressure (MAP) and left ventricular diastolic pressure (LVDP) in the aorta using the right coronary angiography catheter JR3.5 and pigtail angiography catheter, respectively. Then, a percutaneous puncture was performed on the right external jugular vein, and an endocardial pacing electrode was fixed at the apex of the right ventricle (aVL showed an R wave during pacing). The pacemaker was buried subcutaneously in the back of the neck through a subcutaneous tunnel. After good pacing, inject 1.0g of long-acting penicillin intramuscularly and deliver it to the dog's house for normal water feeding. Control dogs were not given pacing after implantation of pacemakers. Observe the general condition and water intake of the dog every day, paying special attention to whether there is limb edema, respiratory distress, and decreased appetite. Measure the above indicators on the 5th, 6th, 7th, and 8th day after pacing to determine whether heart failure has occurred.

　　3. Modeling principle: Rapid right ventricular pacing causes heart failure in animals.

　　4. Changes after modeling: Prior to pacing, all dogs were active, had frequent tail wagging, had upright hair, had no leftover food, bark wildly when seen, and had no edema in their limbs; After 4 days of pacing, there is a decrease in tail wagging activity, hair standing upright, residual food, barking when seen, and no edema in the limbs; After 6 days of pacing, there was a significant decrease in tail wagging activity, hair lodging, about 1/2 leftover food, no barking when seen, still barking when provoked, and no edema in the limbs; After pacing for 8 days, the prone dog has no activity, fallen hair, about 2/3 leftover food, no barking when provoked, and no edema in the limbs; The pacing situation in the control group remained the same for 4, 6, and 8 days.

　　Rapid right ventricular pacing has a significant impact on the hemodynamics and endocrine system of dogs. On the 6th day of pacing, half of the dogs showed significant changes in their hemodynamic and endocrine indicators compared to before pacing, indicating heart failure; On the 7th day of pacing, most dogs showed significant changes in the above indicators; On the 8th day, all dogs showed significant changes in the above indicators.

      5. Precautions: Surgical instruments should be strictly disinfected to prevent surgical infections, surgical trauma should be minimized, and aseptic operation should be strictly enforced.