Exercise training improves the arterial baroreflex function in heart failure rats / 中国病理生理杂志

ABSTRACT

AIM: To investigate the effect of exercise training(EX) on the arterial baroreflex and possible mechanisms in rats with chronic heart failure(CHF).METHODS: Experiments were carried out in four groups EX-CHF,CHF,EX-sham,and sham. CHF was induced by left coronary artery ligation,and EX consisted of 4 weeks of treadmill running. Baroreflex function,plasma angiotensin II(Ang II) and central AT1 receptor expression were determined.RESULTS: (1) The average slope and maximal gain of the baroreflex curve in CHF rats were lower than those in sham rats(P<0.01). EX significantly enhanced baroreflex parameters in CHF group but not in sham group.(2) EX decreased plasma Ang II in CHF rats ［(137±27)ng/L vs (263±55)ng/L,P<0.01］,but had no significant effect on plasma Ang II in sham rats ［(75±17)ng/L vs (92±21)ng/L］.(3) Expression of AT1R protein in the PVN of CHF rats was higher than that in sham rats(1.20±0.21 vs 0.70±0.14,P<0.01). EX reduced AT1R protein level in CHF rats(0.90±0.13),but had no impact in sham rats(0.60±0.16).CONCLUSION: EX restores the attenuated arterial baroreflex function in CHF rats,involving in decrease of plasma Ang II and downregulation of AT1R in the PVN.