Effects of Aerobic Exercise on Skeletal Muscle Glycogen and Exercise Endurance in Rats with Chronic Heart Failure / 中国康复理论与实践

ABSTRACT

Objective To observe the effects of 8-week aerobic exercise on skeletal muscle glycogen content and exercise endurance and investigate the possible mechanism in rats with chronic heart failure. Methods 30 Sprague-Dawley rats were submitted to heart failure sed-entary (H) group, heart failure traning (HT) group and sham operation (S) group. The heart failure model was established with coronary ar-tery ligation. HT group performed an 8-week treadmill running. The skeletal muscle glycogen content was determined with anthracenone, exercise endurance with exhaust duration of graded exhausted exercise test, glucose uptake rate, activity of glycogen synthase (GS) and gly-cogen phosphorylase (GP) with radicisotope, protein expression of total GS, phospho-GS (p-GS), total GP and phospho-GP (p-GP) with Western Blotting. Correlation analysis was conducted between glycogen content and exhaust duration. Results The skeletal muscle glyco-gen, exhaust duration, glucose uptake rate, GS activity and p-GP protein reduced (P<0.05), while serum insulin, GP activity and p-GS pro-tein raised (P<0.05) in the H group compared with those in the S group. The skeletal muscle glycogen, exhaust duration, glucose uptake rate, GS activity and p-GP protein increased (P<0.05), while serum insulin, GP activity and p-GS protein decreased (P<0.05) in the HT group compared with those in the H group. There was positive correlation between glycogen content and exhaust duration (P<0.05). Conclu-sion Prolonged aerobic exercise enhanced skeletal muscle glycogen content and exercise endurance in rats with chronic heart failure, which may be related to the improvement of insulin sensitivity, muscle glucose uptake, increase of glycogen synthesis and decrease of glycogen breakdown.