EXERCISE TRAINING IMPROVE CARDIAC AUTONOMIC CONTROL, CARDIAC FUNCTION AND ARRHYTHMOGENESIS IN RATS WITH PRESERVED EJECTION FRACTION HEART FAILURE

Chronic heart failure is characterized by autonomic imbalance, cardiac dysfunction and arrhythmogenesis. It has been shown that exercise training (ExT) improves central nervous system oxidative stress, autonomic control and cardiac function in heart failure with reduced ejection fraction (HFrEF), however to date no comprehensive studies have addressed the effects of ExT, if any, on oxidative stress in brainstem cardiovascular areas, cardiac autonomic balance, arrhythmogenesis and cardiac function in heart failure with preserved ejection fraction (HFpEF). We hypothesize that ExT reduces brainstem oxidative stress, improves cardiac autonomic control, cardiac function and reduces arrhythmogenesis in HFpEF rats. Rats underwent sham or volume overload to induce HFpEF. ExT (60min/day, 25m/min, 10%inclination) was performed for 6 weeks starting at the second week post-HFpEF induction. Rats were randomly allocated into Sham sedentary (Sham+Sed, n=8), Sham exercise training (Sham+ExT, n=6), HFpEF Sedentary (HFpEF+Sed, n=8); or HFpEF Exercise trained (HFpEF+ExT, n=8) groups. Compared to HFpEF+Sed condition, HFpEF+ExT rats displayed reduced NAD(P)H oxidase activity and oxidative stress in the rostral ventrolateral medulla (RVLM), improved cardiac autonomic balance, and reduced arrhythmogenesis. Furthermore, a 3-fold improvement in cardiac function was observed in HFpEF+ExT rats. These novel findings suggestthat moderate-intensity ExT is an effective means to attenuate the progression of HFpEF through the improvement in RVLM redox state, cardiac autonomic control, and cardiac function.

from Physiology via xlomafota13 on Inoreader http://ift.tt/2rlTJ4g
via IFTTT