Role of angiotensin II type 2 receptor during electrophysiological remodeling of left ventricular hypertrophic myocardium in spontaneously hypertensive rats

摘要

Abstract The objective was to investigate the role of angiotensin II type 2 receptor during electrophysiological remodeling of left ventricular hypertrophic myocardium in spontaneously hypertensive rats (SHRs). A total of 36, aged 10 weeks, male SHRs were divided into three groups: control, valsartan, and valsartan?+?PD123319 groups (n?=?12 in each). The systolic blood pressure, left ventricular mass index, ventricular effective refractory period, and ventricular fibrillation threshold (VFT) were also measured after 8 weeks. At the same time, I Na , I CaL , I to , and membrane capacitance were measured in left ventricular myocytes by whole-cell patch-clamp. The VFT of valsartan was higher than that of control (valsartan vs. control: 17.4?±?0.6?mA vs. 15.8?±?0.5?mA, P ? P ? to of valsartan was?higher than that of control (valsartan vs. control: 14.7?±?0.42 pA/pF vs. 11.2?±?0.15 pA/pF, P ? to of valsartan was higher than that of valsartan?+?PD123319 (valsartan vs. valsartan?+?PD123319: 14.7?±?0.42 pA/pF vs. 13.6?±?0.30 pA/pF, P ? CaL of valsartan was lower than that of control (valsartan vs. control: ?4.6?±?0.2 pA/pF vs. ?6.9?±?0.1 pA/pF, P ? CaL of valsartan was lower than that of valsartan?+?PD123319 (valsartan vs. valsartan?+?PD123319: ?4.6?±?0.2 pA/pF vs. ?5.4?±?0.1 pA/pF, P ? Highlights ? The activation of angiotensin II type 2 receptor (AT2R) improved the density of I to . ? The stimulation AT2R decreased the density of I CaL . ? The stimulation of AT2R reduced the left ventricular mass index. ? The stimulation of AT2R decreased the membrane capacitance of cardiomyocyte. ? The stimulation of AT2R improved the ventricular fibrillation threshold.