大剂量、短时间补充肌酸停止后大鼠内源性肌酸生物合成恢复的动态观察  

Observation on Dynamic Recovery Process of the Endogenous Biosynthesis of Creatine after Short Term Creatine Supplementation in Rats

作　　者：李显[1] 艾华[1] 李莉 

机构地区：[1]北京大学第三医院运动医学研究所,北京100083 [2]河北师范大学体育学院

出　　处：《中国运动医学杂志》2005年第4期434-438,442,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:探讨大剂量、短时间补充肌酸停止后,大鼠内源性肌酸生物合成的恢复。方法:大鼠补充大剂量(3.0g/kg/d)肌酸1周后停止,动态观察内源性肌酸生物合成代谢途径中限速酶活力和主要代谢物质含量的变化。结果:大剂量、短时间补充肌酸引起的肾脏精氨酸-甘氨酸脒基转移酶(AGAT)活力下降,可在停补肌酸后8天内恢复正常;补充肌酸引起的肾脏和肝脏胍乙酸含量降低也分别于停补肌酸后4天和8天内恢复正常;补充肌酸导致的各组织器官肌酸含量升高均在8天内恢复正常,其中肾脏1天,血清3～4天,比目鱼肌4天,腓肠肌8天;升高的血清肌酐含量于1天内恢复正常。组织肌酸激酶(creatinekinase,CK)活力未受到补充肌酸的影响。结论:停止大剂量、短时间补充肌酸后,大鼠自身的肌酸生物合成到8天左右可逐渐恢复正常。这表明,大剂量、短时间补充肌酸对内源性肌酸合成的抑制作用可在去除抑制因素后较短时期内得到逆转。Objective To explore the recovery process of endogenous biosynthesis of creatine after short term high-dose of creatine supplementation. Methods After oral creatine supplement at a dose of 3.0g/kg/d for 1 week, the dynamic changes of the activity of arginine:glycine amidinotransferase (AGAT), the rate-limiting enzyme, and the contents of main metabolites in the pathway of creatine endogenous biosynthesis in rats were observed. Results The decreased AGAT activity in kidney caused by creatine supplementation increased to normal level within 8 days, and the reduced guanidinoacetic acid contents in kidney and liver returned to normal within 4 and 8 days, respectively, after ceasing the exogenous creatine. All the increased creatine concentrations in the tissues and organs measured returned to normal within 8 days: 1 day in kidney, 3～4 days in serum, 4 days in soleus, and 8 days in gastrocnemius. The increased serum creatinine contents went down to control level within 1 day. The creatine kinases activities were not affected by creatine supplementation. Conclusions After short-term creatine supplementation with a high dose, the endogenous biosynthesis of creatine was able to recover gradually around 8 days. This indicated that the inhibitory effect of large amount of exogenous creatine supplementation for a short period of time on the endogenous biosynthesis of creatine could be eliminated after removing the inhibitive factor.

关 键 词：生物合成 动态观察 大剂量 内源性 恢复 时间 大鼠 物质含量 代谢途径 基转移酶 组织器官 比目鱼肌 肌酐含量 肌酸激酶 抑制因素 抑制作用 酸含量 酶活力 甘氨酸 精氨酸 肾脏 腓肠肌 升高 血清 

分 类 号：R87[医药卫生—运动医学]