经皮穴位电刺激对力竭运动大鼠血浆超氧化物歧化酶和丙二醛的影响

目的:观察经皮穴位电刺激(TEAS)对力竭运动大鼠的抗运动性疲劳效应,初步探讨其抗氧化机制。方法:采用5级递增跑台运动建立力竭运动大鼠模型。27只雄性SD大鼠随机分为安静对照组(n=9)、运动组(n=9)和TEAS组(n=9)。TEAS治疗选穴"足三里",电针参数:施以连续波,频率2 Hz,强度5 mA,时间30 min,左右交替,每日1次,连续治疗7 d。力竭运动后,记录大鼠力竭运动时间,用乳酸氧化酶法测定血浆乳酸水平,黄嘌呤氧化酶法测定血浆超氧化物歧化酶(SOD)活性,硫代巴比妥酸法检测血浆丙二醛(MDA)含量。结果:①TEAS组力竭运动时间显著长于运动组(P<0.05)。②运动组血浆乳酸显著高于安静对照组(P<0.05)和TEAS组(P<0.05)。③与安静对照组比较,运动组大鼠血浆SOD活性无显著性变化,但MDA含量升高却十分显著,差异有显著性意义(P<0.01),其SOD/MDA比值显著降低(P<0.05);TEAS组SOD活性显著高于安静对照组和运动组(P<0.01),MDA含量显著低于运动组(P<0.05),其SOD/MDA比值明显高于运动组(P<0.01)。结论:TEAS"足三里"穴可有效抗运动性疲劳,可能是通过其减少血乳酸堆积、提高机体抗氧化能力、减少脂质过氧化反应实现的。

Effects of Transcutaneous Electric Acupoint Stimulation on Plasma SOD and MDA in Rats with Sports Fatigue

OBJECTIVE: To observe the effect of transcutaneous electric acupoint stimulation (TEAS) on plasma superoxide dismutase (SOD) and malondialdehyde (MDA) in rats with sports fatigue so as to explore its mechanisms in resisting exercise-induced fatigue. METHODS: Twenty-seven male adult SD rats were randomly divided into control group (n 9), model group (n=9) and TEAS group (n=9). Sports fatigue model was established by using treadmill method, i.e. forcing the rat to run 10 min at a speed of 10 m/min, 15 m/min, 20 m/min, 24 m/min and 28 m/min, once daily for 6 days. TEAS (continuous waves, 2 Hz, 5 mA) was applied to unilateral "Zusanli" (ST 36) for 30 min, once per day for 7 days. The exhausted exercise time from starting running to exhaustion was recorded on the 7th day and the lactate levels, SOD activity and MDA contents in plasma were measured by lactate oxidase method, xanthine oxidase method and thiobarbituric acid method respectively. RESULTS: The duration of exhausted exercise in model group and TEAS group were (56.00 +/- 12.27) min and (70.88 +/- 13.74) min respectively, displaying significant increase in exercise tolerance after TEAS (P<0.05). The lactate level and MDA content in model group were markedly higher than those in control group (P<0.05); while compared with model group, lactate and MDA contents in TEAS group were significantly lower (P<0.05), and plasma SOD activity in TEAS group was significantly higher (P<0.01). No significant differences were found in plasma lactate content between control and TEAS groups and in SOD activity between model group and control group (P>0.05). SOD/MDA of model group was significantly lower than those of control group and TEAS group (P<0.05, 0.01). CONCLUSION: TEAS at "Zusanli"(ST 36) can effectively postpone exercise-induced fatigue by reducing accumulation of blood lactate, improving anti-oxidative ability and relieving lipid peroxidation in the rat.