补充肌酸及间歇性运动对大鼠内源性肌酸合成的影响

目的:探讨补充大剂量肌酸对运动大鼠自身肌酸合成的影响.方法:补充肌酸的大鼠进行短时间大强度的间歇性跑台运动,观察对肾脏精氨酸-甘氨酸脒基转移酶(AGAT)活性、胍乙酸含量、骨骼肌肌酸含量和血清肌酸含量的影响.结果:补充相当于人体冲击剂量(1.5 g/kg/d)的肌酸对短时间大强度运动的大鼠肾脏AGAT活性和肝脏胍乙酸含量并不产生明显的影响;而补充超大剂量肌酸,均可引起运动大鼠肾脏AGAT活性和肝脏胍乙酸含量明显下降(P<0.01);超大剂量补充肌酸引起运动大鼠血清肌酐含量增加(P<0.01).

Effect of Creatine Supplementation and Interval Exercise on Endogenous Biosynthesis in Rats

Objective: The purpose of this study was mainly to study the effects of creatine supplementation on endogenous biosynthesis and metabolism of creatine in exercise-training rats.Methods: After treated with variable doses of creatine,the activities of L-arginine glycine amidinotransferase(AGAT),the concentration of guanidinoacetic acid(GA)in kidney,the concentration of creatine in skeletal muscles and serum in the exercise and control rats were measured.Results: The training rats following creatine supple-mentation at doses of 1.5 g/kg/d(equal to the loading dose for human)did not affect the AGAT activity in kidney and guanidinoacetic acid content in liver compared with control group,and creatine supplementation at doses of 6.0g/kg/d had significantly(P<0.01)lower AGAT activity in kidney and guanidinoacetic acid content in liver than the training rats without creatine supplement.The dose of 6.0 g/kg/d creatine supplementation could increase serum creatinine level(P<0.01).