Effects of valsartan and/or spironolactone on myocardial remodeling in the spontaneous hypertensive rats

Objects To observe the inhibitory effects on the renin-angiotensin-aldosterone system by using valsartan and/or spironolactone in the spontaneous hyepertensive rats (SHRs). Methods Thirty-two SHRs were randomly divided into 4 groups:SHR-P(Placebo), SHR-S(treated with spironolactone), SHR-V(treated with valsartan) and SHR-C(treated with combination of spironolactone and valsartan). Systolic blood pressure(SBP), left ventricular mass index(LVMI), myocardial collagen contents(MCC), collagen volume fraction(CVF), plasma and myocardial aldosterone concentration were measured.Results Compared with SHR-P, SBP was decreased in SHR-V(P0.05) and SHR-C(P0.01), respectively. LVMI, MCC and CVF were decreased similarly in the three treatment groups (P0.05). Compared with SHR-P, plasma and myocardial aldosterone concentration in SHR-V were decreased (P0.05); plasma aldosterone concentration in SHR-S was significantly increased (P0.05),while myocardial aldostereone concentration was significantly decreased (P0.01).Myocardium aldosterone concentration in SHR-C was decreased (P0.01). Conclusion This study shows long-term administration of Angiotensin Ⅱ type 1 receptors (AT1) antagonist can cause plasma and myocardial aldosterone escape in hypertensive cardiovascular tissue.The combining use of valsartan and spironolactone can normalize myocardial aldosterone and ventricular remodeling.