茶氨酸延缓运动性疲劳及其作用机制研究

目的:研究茶氨酸延缓运动性疲劳的作用,并探讨相关的机制。方法:160只小鼠分成4组,三个剂量组分别以茶氨酸5.6、8.4和12.6mg/(kgbw?d)灌胃,对照组以等量蒸馏水灌胃,连续30d。实验期末进行负重游泳试验,测定血清尿素氮(BUN)、肝糖原及脑组织中5-羟色胺(5-HT)、多巴胺(DA)、去甲肾上腺素(NE)等单胺类神经递质含量。结果:中、高剂量组的负重游泳时间和肝糖原含量均显著高于对照组(P<0.05);运动后中剂量组BUN增加量显著低于其他各组,休息60min后各剂量组BUN含量明显低于对照组(P<0.05);运动前、后各剂量组5-HT含量低于对照组,运动前中剂量组和运动后中、高剂量组DA含量高于对照组,运动前各剂量组和运动后中剂量组DA/5-HT比值高于对照组,差异均有显著性(P<0.05)。结论:茶氨酸具有延缓运动性疲劳作用,其机制可能与茶氨酸增加脑组织中DA含量,抑制5-HT的合成和释放等效应有关。

EFFECT OF THEANINE ON DELAYING EXERCISE-INDUCED FATIGUE AND ITS MECHANISM

Objective: To study the effect of theanine on delaying exercise-induced fatigue, and reveal its possible mechanism.Method: Mice were randomized into 4 groups:three groups of theanine at doses of 5.6、8.4、12.6 mg/(kg bw·d),and one control group given distilled water.After 30 d,burdened swimming time,serum BUN,liver glycogen,and monoamine neurotransmitters(5-HT、DA and NE) concentrations in brain were measured.Results: Compared with the control group,both the burdened swimming time and the liver glycogen level of 8.4、12.6mg/(kg bw·d)groups increased significantly (P<0.05).All the three theanine groups showed lower serum BUN levels and faster BUN elimination than the control group 60 min after swimming(P<0.05).8.4 mg(/kg bw·d)group displayed the least increment of serum BUN. The three theanine groups also showed obviously lower 5-HT levels than the control group in both swimming and non-swimming state(P<0.05).The 8.4 mg(/kg bw·d)group in non-swimming mice and 8.4、12.6 mg/(kg bw·d)groups in swimming mice displayed higher DA levels than the control group. The DA/5-HT ratio of three theanine groups in non-swimming mice and the 8.4 mg/(kg bw·d)group in swimming mice were higher than that in control group(P<0.05).Conclusion: Theanine has the effect of delaying exercise-induced fatigue possibly through enhancing DA level and inhibiting the synthesis or secretion of 5-HT in brain.