补充精氨酸对过度训练大鼠肌糖原、AMPK及GLUT-4的影响

Effect of Supplying L-arginine on Skeletal Muscle Glycogen, AMPK Activity and Sarcolemma GLUT4 Protein Contents in Overtraining Rats

目的:观察体外补充L-精氨酸对过度训练大鼠的作用。方法:9周龄SD雌性大鼠40只,随机分为安静对照组(A组)、大强度运动组(B组)、大强度运动服L-精氨酸组(C组)、过度训练组(D组),其中D1组为过度训练组,D2组为过度训练加服L-精氨酸组。上坡跑训练9周后测各组白腓肠肌和比目鱼肌的肌糖原含量、AMPK活性和肌膜GLUT-4含量。结果:B组和D1组糖原含量较A组有升高趋势,但无显著性;C组显著高于A组(P<0.01);D2组大鼠比目鱼肌糖原含量较A组显著升高(P<0.01);D2组较D1组升高,但未达到显著水平(P>0.05)。B组、C组和D2组AMPK活性显著高于A组(P<0.01);D2组较D1组有明显增加,差异显著(P<0.05)。B组、C组和D2组GLUT-4含量分别较A组增加100%左右,D1组增加11%;D2组较D1组增加57%。结论:体外补充L-精氨酸可能有利于延缓或治疗过度训练。

Objective： The purpose of the present study was to observe effect of supplying L-arginine on skeletal muscle glycogen contents,AMP-activated protein kinase（AMPK） activity and sarcolemma Glucose transporter type 4（GLUT4） protein contents in overtraining rats.Methods： Forty SD rats were randomly divided into group A（sedentary）,group B（underwent endurance exercise 60 minutes/day）,group C（underwent endurance exercise 60 minutes/day,supplying L-arginine） and group D（underwent endurance exercise 120 minutes/day）,group D subdivided group D1（without L-arginine） and group D2（with L-arginine）.All exercise groups were trained 6 days/wk for 9 weeks.Muscle glycogen,sarcolemma GLUT4 contents and muscle AMPK activity were determined after the 9-week training.Results： Muscle glycogen contents in group B and group D1 exist a trend of increase compared with that in group A,but not significantly（P0.05）.Muscle glycogen contents in soleus showed a significant higher level in group C and group D2 compared with that in group A（P0.01）,and it showed a trend of increase in group D2 compared with that in group D1,but not significantly（P0.05）.Muscle AMPK activity in group B,group C and group D2 increased significantly compared with that in group A,and it showed a significant higher level in group D2 compared with that in group D1（P0.01）.Sarcolemma GLUT4 contents in group B,group C and group D2 increased about 100% compared with that in group A,but it only increased 11% in group D1.And that increased by 57% in group D2 as compared with that in group D1.Conclusion： Supplying with L-Arg could increase muscle glycogen cotents,muscle AMPK activity,and sarcolemma GLUT4 content in overtraining rats,which might be helpful in staying or treating overtraining.