【Animal Modeling】-Mice Acute Myocardial Infarction Model
动物造模,急性心肌梗死
z-bo
2022-01-13
508
1. Experimental animals are usually male rats weighing about 300 g.
2. The model is made by intraperitoneal anesthesia, 5% sodium pentobarbital (50 mg/kg), and fixed on the operating table in the supine position. The apex of the rat touches the intercostal space with the most pulsation, cuts the skin and intercostal muscles, squeezes the heart, finds the anterior descending branch at the junction of the pulmonary artery cone and the left atrial appendage, and ligates it with a silk thread 2 mm from the root, quickly compressing the chest cavity Ribs until the animal resumes spontaneous breathing, suture the muscles and skin of the chest wall (hint: the left coronary artery originates from the aorta and is close to the left end of the pulmonary sinus). It is located between the pulmonary sinus and the left atrial appendage, forming a diagonal line from head to tail 2– 3 mm, then bifurcated, buried in the subpericardial myocardium, usually invisible. Then, thread the silk thread through the pulmonary sinus and connect it from the pulmonary vein to the end of the left atrial appendage 2 mm from the pulmonary valve, pass through the center of the silk thread and suture about 5 mm of the myocardium to secure the artery. The ligation should be fast to minimize the time the heart is placed outside the chest
3. Evaluation of research results
(1) Assessment of cardiac function: When connected to a multi-channel physiological recorder, the carotid artery cannula can record heart rate, blood pressure, left ventricular pressure, and isovolumic systolic pressure (dp/dt). , Small animals can provide special ultrasound equipment to detect heart function, which can ensure that long-term experiments are required
(2) General pathology: usually tetrazolium blue (TTC semi-quantitative assessment of infarcted myocardial area (using staining). Before the animal is sacrificed, 0.5% Evans blue solution is injected through an intravenous cannula, and normal myocardium is stained blue The ischemic myocardium was not stained. The animal was sacrificed. The heart was quickly taken out, and the water was absorbed with filter paper. It was placed in a refrigerator at -20°C for 20 minutes and then taken out. The longitudinal axis of the left ventricle was adjusted to 2-3 mm. Thin slices, soaked in 2% TTC solution, incubated in a 37°C water bath for 30 minutes, the ischemic myocardium is stained with red bricks, and myocardial infarction is not stained. Weigh each myocardial section, take an image of the section, and use the image The analysis system analyzes the color of each slice, expresses it as a percentage of the infarct area in the total area of the left ventricle, and obtains a weighted average of all slices.
(3) Histology: According to your research needs, choose immunohistochemistry, immunofluorescence and other methods to detect the target substance.
