A Protocol for Constructing a Mouse Model of Hypertensive Myocardial Fibrosis Using Angiotensin II

The continuous infusion of Angiotensin II (Ang II) via osmotic pumps is a widely utilized approach for establishing animal models of hypertensive myocardial fibrosis. Nevertheless, this technique exhibits certain limitations in current reports, such as the instability of Ang II, inaccurate pump placement, and the lack of a standardized procedure. Current reports on the methodology for establishment remain relatively limited. This protocol has systematically optimized the establishment of Ang II osmotic pump-induced hypertensive myocardial fibrosis models in mice, including the standardized preparation of Ang II solution, calibration of dosage, precise subcutaneous implantation of osmotic pumps, and quantitative standards for model evaluation indicators. Experimental results demonstrated that Ang II osmotic pump-induced hypertensive myocardial fibrosis in mice with high survival rates. Systolic blood pressure (SBP) levels stabilized at 160 mmHg after seven days of subcutaneous implantation. The model mice had significantly reduced left ventricular ejection fractions and increased end-diastolic dimensions of the left ventricle. Compared with the sham surgery group, collagen deposition within hypertensive myocardial interstitial tissue and perivascular regions increased. This study, based on a small sample size (n = 6), preliminarily validated the feasibility of establishing a mouse model of hypertensive myocardial fibrosis using Ang II combined with an osmotic pump, and established a quantitative phenotype verification system.