补充肌酸对生长发育期雌、雄大鼠内源性肌酸合成的影响  

Effects of Creatine Supplementation on Endogenous Creatine Synthesis in Female and Male Rats in the Period of Growth and Development

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》2008年第1期61-66,共6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:探讨补充肌酸对生长发育期雌、雄大鼠内源性肌酸合成的影响,为不同群体合理使用肌酸提供实验依据。方法:21天龄雌性和雄性SD大鼠随机分为5组,每组雌、雄大鼠各6或7只,分别连续补充0(对照液)、0.15、0.35、0.75或1.5g/kg/d肌酸液8周。观察内源性肌酸合成代谢途径中L-精氨酸-甘氨酸脒基转移酶(AGAT)活性和其它主要指标的变化。结果:与相同性别对照组相比,雌性或雄性大鼠补充肌酸8周后,肾脏AGAT活性和肝脏胍乙酸含量均降低,且补充肌酸剂量越大,降低越明显;腓肠肌、跖肌和比目鱼肌肌酸含量、血清肌酐含量升高;肾脏结构无明显差异。补充相同剂量肌酸的雄性大鼠肾脏AGAT活性和肝脏胍乙酸含量均高于雌性大鼠。结论:补充肌酸对生长发育期雌性或雄性大鼠的内源性肌酸合成均有抑制作用。雌性大鼠内源性肌酸合成能力弱于雄性。补充肌酸有助于提高骨骼肌肌酸含量。大剂量(1.5g/kg/d)补充肌酸不会对肾脏结构产生明显影响。Objective To explore the effects of creatine supplementation on endogenous creatine synthesis in female and male rats in the period of growth and development to provide experimental data for utilizing creatine rationally in various human groups. Methods Both 21-day-old female or male SD rats were employed and divided randomly into 5 groups with creatine supplementation of 0（control）, 0.15, 0.35, 0.75 and 1.5g/kg/d, respectively, for 8 weeks. Each sex had 6 or 7 rats in each group. L-arginine..glycine amidinotransferase （AG- AT） activity in kidney and the other main metabolic indexes in creatine biosynthesis were determined. Results As compared with the same gender control group, AGAT activities in kidney and guanidinoacetic acid （GAA） contents in liver of female or male rats supplemented with creatine for 8 weeks were decreased in a dose-dependent way. Creatine contents in gastrocnemius, plantaris or soleus, and creatinine content in serum were increased by creatine supplementation. There were not significant differences in kidney structures between creatine supplemented groups and controls of the same gender. As compared with the female rats supplemented with same doses of creatine, the male rats had higher AGAT activities in kidney and GAA contents in liver. Conclusions Endogenous creatine syntheses were inhibited by creatine supplementation both in female and male rats in the period of growth and development. Female rats have a weaker ability to synthesize endogenous creatine than male rats. Creatine supplementing can conduce to higher creatine content in skeletal muscles. Kidney structure was not markedly affected by the large dose （1.5g/kg/d） of creatine supplementation.

关 键 词：肌酸补充 L-精氨酸-甘氨酸脒基转移酶 雌性大鼠 雄性大鼠 生长发育 

分 类 号：R87[医药卫生—运动医学] R783.5[医药卫生—临床医学]