Electroacupuncture Improves Cardiac Function And Remodeling By Inhibition Of Sympathoexcitation In Chronic Heart Failure Rats

Background:Chronic heart failure (CHF) has become a major clinical and public health challenge, which is responsible for significant morbidity and mortality worldwide, mainly as a result of cardiac remodeling caused by neurohumoral activation including sympathetic nervous system and renin-angiotension system. Suppression of neurohumoral activation could reverse the cardiac remodeling and improve the cardiac function. Acupuncture has been used to treat a wide range of diseases and conditions including hypertension, arrhythmia and pain. It has been reported that electroacupuncture (EA) could lower sympathetic activity and significantly inhibit the cardiovascular sympathoexcitatory reflex responsesObjective:In this study, we investigated the effects of electroacupuncture (EA) on the sympathetic nerve activity, heart function and remodeling in CHF rats after ligation of the left anterior descending coronary artery.Methods:CHF rats were randomly selected to EA and control groups for acute and chronic experiments. In the acute experiment, both the renal sympathetic nerve activity (RSNA) and cardiac sympathetic afferent reflex (CSAR) elicited by epicardial application of capsaicin were recorded, at the same time, EA was performed for30minutes to examine that the effects of EA on sympathetic activity. In the chronic experiment, we performed EA for30minutes once a day for1week to test the long-term EA effects on heart function and remodeling as well as infarct size in CHF rats. For further confirmation and comparison with the effects of EA on heart performance, the effective β1-selective blocker, metoprolol, was used as a control.Results:The results show EA significantly decreased the RSNA effectively, inhibited CSAR and lowered the blood pressure of CHF rats. Treating CHF rats with EA for1week dramatically increased left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS); and reversed the enlargement of left ventricular end-systolic dimension (LVESD) and left ventricular end-diastolic dimension (LVEDD); and shrunk the infarct size, which is comparable to the effects of metoprolol on improvement in CHF rats.Conclusions:In this experiment, we demonstrated EA attenuates sympathetic overactivity. Additionally, long-term EA improves cardiac function and remodeling and reduces infarct size in CHF rats. EA is a novel and potentially useful therapy for treating CHF.