Objective: To establish a fast and efficient method for measuring right ventricular pressure in mice without the aid of a ventilator and easy to operate, and to explore the measurement techniques. Methods: 23 C57BL/6J mice (8 weeks old) were randomly divided into a hypoxic group (11) and a control group (12). The hypoxic group was raised in a hypoxic chamber (10% O2) for 4 weeks to prepare pulmonary hypertension The model and the control group were raised in normal air, and other conditions were the same. After the model was prepared, a 0.6×25mm disposable infusion set needle was used to directly puncture the right ventricle through the intercostal muscle in the closed state of the mouse chest cavity, and the right ventricular systolic pressure (RVSP) was measured by a multi-lead physiometer, and the chest was opened to verify the puncture point Calculate the right ventricular hypertrophy index (rightventricularhypertrophyindex, RVHI=RV/(LV+S) by weighing the weight of the right ventricle (rightventricular, RV), left ventricular+septum, LV+S) × 100%, the left lung was taken for pathological section and stained with hematoxylinandeeosin (HE) and α-smoothmuscle actin (α-SMA) to observe the structural changes of pulmonary artery.
Result: The right ventricle was directly punctured through the intercostal muscles to obtain the right ventricular pressure curve. The whole process was completed within 3 to 4 minutes. The success rate of RVSP determination was 95.6% (1 in the control group failed). The RVSP and RVHI of the hypoxia group were (30.48±2.95) mmHg and (35.31±3.78)%, respectively, which were significantly higher than those of the control group (17.50±3.40) mmHg and (23.14±4.29)% (both P<0.05). The walls of small pulmonary arteries in the hypoxia group were significantly thickened and the smooth muscles of the media proliferated. Conclusion: The method of measuring the pressure curve of the right ventricle of mice by intercostal muscle puncture keeps the animal's chest tightly closed without the need for ventilator-assisted ventilation. It is simple and quick, and can quickly assess the hemodynamic status of the right ventricle of mice. The success rate is high and it is worthy of promotion.