热环境对力竭游泳运动恢复期大鼠下丘脑细胞外液单胺类神经递质的影响

Effect of Thermal Environment on Hypothalamic Extracellular Fluid Monoamine Neurotransmitter in the Recovery Period after Exhaustive Exercise

观察大鼠在热环境中进行力竭游泳运动后24h恢复期下丘脑细胞外液单胺类神经递质含量的动态变化,分析其变化特点与相互关系,为探索热环境下运动性中枢疲劳的产生和恢复机制提供实验依据。方法:将32只SD雄性大鼠随机分成常温安静组、常温力竭组、高温安静组、高温力竭组,采集运动后4h、5h、6h、8h及24h微透析样品,并采用毛细管电泳-激光诱导荧光法检测单胺类神经递质含量。结论:热环境下大鼠力竭运动恢复期下丘脑细胞外液5-羟色胺(5-HT)含量与常温力竭运动相比升高更加显著,介导核心温度的升高;而多巴胺(DA)和去甲肾上腺素(NE)含量的降低,导致机体对热的耐受性降低;高5-HT浓度、高核心温度和机体低热耐受性的共同作用,加快中枢疲劳的发生,降低机体运动能力。

Objective： To observe the dynamic changes of hypothalamic extracellutar Fluid Monoamine Neurotransmitter in thermal environment in the 24-hour recovery period after exhaustive swimming and analyze the change characteristics and interrelations so as to provide experimental reference for exploring the occurrence of exercise-induced central fatigue in thermal environment and the recovery mechanism. Method： 32 SD male rats were divided randomly into the quiet room-temperature group, exhaustive-exercise room-temperature group, quiet thermal-environment group and exhaustive-exercise thermal-environment group. Micro-dialysis samples were collected 4h, 5h, 6h, 8h and 24 hours after the exercise. The samples were determined by CE-LIF for the content of monoamine neurotransmitter. Conclusion： 5-HT level in thermal environment after exhaustive exercise is obviously higher than that in room temperature after exhaustive exercise, mediating the increase of the core temperature. The decrease of DA and NE levels results in reducing the heat tolerance of body. The combined eftbcts of high 5-HT concentration, high core temperature and low heat tolerance of body accelerate the occurrence of central fatigue and reduce the exercise performance of body.