高温高湿环境下递增负荷大强度运动对人体血清白细胞介素12的影响

Exhaustive Exercise under Hot and Humid Environment Decreases Human Serum Interleukin-12

目的:探讨高温高湿环境下大强度运动对人体血清白细胞介素12(interleukin-12,IL-12)的影响。方法:20名受试者随机分为运动组和暴露组,运动组在温度33℃、相对湿度分别为40%±2%(RH40%)和80%±2%(RH80%)的环境下进行递增负荷力竭跑台运动,两次不同湿度运动间隔1周。跑速从8 km/h开始,每分钟增加0.8 km/h,增加到16 km/h时不再增加,然后逐级递增坡度,以0.5%为起始坡度,实验过程中以受试者不能维持相应跑速,并自述不能坚持时终止运动。暴露组在高温中静坐,两者同时进出高温环境房。实验前和实验后即刻抽取静脉血。采用ELISA方法检测血清IL-12、皮质醇。结果:运动组RH40%和RH80%环境下运动后IL-12均显著性降低(P<0.05);暴露组IL-12在RH40%暴露后出现降低趋势,RH80%暴露后显著性下降(P<0.05)。运动组RH40%和RH80%环境下运动后血清皮质醇均显著升高(P<0.01,P<0.05);暴露组血清皮质醇RH40%暴露前后无显著性差异,RH80%暴露后显著性降低(P<0.01)。结论:高温环境下,无论相对湿度高低,进行递增负荷大强度运动后血清IL-12均降低,可能由血清皮质醇显著升高对IL-12产生抑制作用所引起,但高温环境下运动引起免疫抑制的机制有待研究。

Objective To observe the changes in serum interleukin-12（IL-12）before and after exhaustive exercise in hot and humid environment. Methods 20 subjects were randomly divided into exercise group and expose group. Subjects in exercise group completed incremental exhaustive treadmill exercise twice with an interval of 1 week under the environment with temperature of 33℃ and the relative humidity of 40% and 80%relatively. Subjects in exposure group stayed quietly under the same environment as the exercise group. Blood samples of all subjects were collected before and after the exercise or exposure,and serum IL-12 and cortisol were detected by ELISA. Results The serum IL-12 in exercise group decreased significantly after exercise under the relative humidity of either 40% or 80%,while in exposure group under relative humidity of 40%trended to decrease and under 80% decreased significantly after the exposure. The serum cortisol increased significantly after exercise in exercise group,while in exposure group decreased significantly under relative humidity of 80% before and after the exposure. Conclusions Decreased serum IL-12 after exhaustive exercise under hot and humid environment probably caused by the depressant effect of elevated cortisol level.