Effects of Spironolactone on the Left Ventricular Remodeling In Renovascular Hypertension Rats

Objective To investigate the effects of spironolactone on the myocardial fibrosis and left ventricular remodeling during the development of left ventricular hypertrophy (LVH) in renovascular hypertension rats. Methods Two-kidney, one-clip (2K1C) renovascular hypertension was induced in Sprague-Dawley rats. The rats were randomized to non-intervention group (N group), spironolactone group (S group) that gorged spironolactone 50mg·kg-1-d-1. The sham-operated rats served as control group (C group). The changes of heart structure and function in all groups were observed with echocardiogram. The concentration of angiotensin Ⅱ (Ang Ⅱ) and aldosterone (ALD) in left ventricle were assessed by radioimmunoassay. The Woessner's method was used to estimate the collagen content in left ventricle. Results After 8 weeks treatment, blood pressure, LVEDD, LVPWD, RWT , LVM, LVM1, MESS and mFS in S group decrease slightly compared with N group (P0.05). The concentration of Ang Ⅱ in S group is much lower than in N group (5.86±3.50 ng/g vs 8.10±2.64 ng/g; P0.05). The collagen content (4.49±0.98 mg/100mg vs 5.46±1.12 mg/100mg; P0.01), PVCA(24.68±4.62% vs 35.28±5.80%; P0.01) and CVF (2.18±0.20% vs 3.26±0.28%; P0.01) in S group are much lower than in N group. Conclusion: (1) Renovascular hypertension, LVH, myocardial fibrosis and left ventricular dysfunction can be developed in 2K1C rats. (2) Spironolactone is very effective in reducing myocardial fibrosis, but has weak effects on blood pressure and suppressing the changes of structure and function of left ventricular in renovascular hypertension rats.