长期(8个月)补充肌酸对大鼠内源性肌酸合成的影响  

Effects of Long-Term Supplementing Creatine on the Endogenous Creatine Synthesis in Rats

作　　者：李显[1] 肖海涛[1] 艾华[1] 

机构地区：[1]北京大学第三医院运动医学研究所,北京100083

出　　处：《中国运动医学杂志》2007年第6期700-703,共4页Chinese Journal of Sports Medicine

基　　金：2000~2001年国家体育总局应用基础研究课题(课题编号:01061)资助

摘　　要：目的:探讨长期(8个月)补充肌酸对大鼠内源性肌酸合成的影响。方法:21天龄雄性SD大鼠连续补充0.35g/kg/d肌酸(肌酸组)或对照液(对照组)8个月,观察其内源性肌酸生物合成途径中L-精氨酸-甘氨酸脒基转移酶(AGAT)活性和主要代谢物质含量的变化。结果:8个月后,与对照组相比,肌酸组大鼠肾脏L-精氨酸-甘氨酸脒基转移酶活性显著降低,肾脏、肝脏和血清胍乙酸含量较低;肾脏、肝脏、血清和腓肠肌肌酸含量变化不明显,比目鱼肌和跖肌肌酸含量显著升高;肾脏结构、血清肌酐含量和骨骼肌肌酸激酶活性等均无显著性差异。肾脏AGAT活性与肾脏肌酸含量和血清肌酸含量均无显著相关关系(P>0.05)。结论:长期补充0.35g/kg/d肌酸可抑制大鼠内源性肌酸合成,提高骨骼肌肌酸含量,但不会对肾脏结构产生影响。Objective To explore the effects of long--term （8 months） supplementation of creatine on the endogenous creatine synthesis in rats in order to provide experimental data for supplying creatine more rationally, effectively and safely. Methods SD rats （aged 21 days） were served as objects in this study and were supplemented with 0.35g/kg/d of creatine or control solution. L--arginine： glycine amidinotransferase （AGAT） activity in kidney and other variables of the creatine metabolism within body were determined. Results As compared with the control, AGAT activity in kidney in rats supplemented with 0. 35g/kg/d of creatine for 8 months was significantly lower, and guanidinoacetic acid （GAA） concentrations in kidney, liver and serum were also lower. Significant increase in creatine level was shown in soleus and plantaris in the creatine supplementation group. However, there were not remarkable changes in creatine level in kidney, liver, serum and gastrocnemius in this group, as compared with the control. The histological structure of kidney, creatine concentration in serum and creatine kinase （CK） activity in skeletal muscles in rats supplemented with creatine were almost similar to those in the control rats. And there were no significant correlations between kidney AGAT activity and creatine levels in kidney and serum （P〉0.05）. Conclusion Endogenous creatine synthesis was inhibited by extraneous creatine at the dose of 0.35g/kg/d for 8 months in rats. Creatine levels in skeletal muscles were increased and kidney histological structure was not affected by creatine supplementation.

关 键 词：肌酸 L-精氨酸-甘氨酸脒基转移酶 大鼠 

分 类 号：R87[医药卫生—运动医学]