| 摘要: |
| 目的：探讨一次及多次高温预处理对递增负荷至力竭运动后人血液白细胞 HSP70mRNA及自由基代谢的影响。方法：受试者随机分为运动对照组（C），一次高温预处理组（P1），多次高温预处理组（P2）。P1组进行一次性高温预处理1 h（桑拿，温度46±1 ℃，湿度85%-90%，体重下降2%）。P2组每隔三天进行一次（共八次）高温预处理。C组采用Bruce方案在跑台上进行递增负荷运动至力竭。P1和P2组高温预处理结束，在室温下恢复24 h后，在跑台上进行递增负荷运动至力竭。运动结束后记录最大心率、最大运动通气量、最大摄氧量、呼吸商等，同时记录通气阈时的通气量、最大摄氧量利用率等。C组、P1组及P2组于运动前、运动后即刻、运动后1 h分别采肘静脉血。采用RT-PCR法检测受试者血液白细胞HSP70mRNA表达，用硫代巴比妥（TBA）法测定血清丙二醛（MDA）含量，用黄嘌呤氧化酶法测定血清超氧化物歧化酶（SOD）活性，采用全血乳酸分析仪测定血乳酸值。结果：C组力竭运动后即刻，人血液白细胞HSP70mRNA表达和血清MDA含量较安静时显著增加（P<001，P<005）。C组运动后1 h，HSP70mRNA表达及MDA含量较运动后即刻显著减少（均P<005），而血清SOD活性较运动后即刻显著下降（P<005）。P1组在安静时、运动后即刻及运动后1 h，均较C组相同时间点的HSP70mRNA显著升高（均P<005）。而P1组在运动后1 h较C组同时间点的SOD活性显著升高（P<005）。P2组血液在运动后即刻和运动后1 h，均较C组相同时间点的HSP70mRNA表达及血清SOD活性显著升高（均P<005）。而P2组在安静、运动后即刻及运动后1 h较C组同时间点的MDA含量均显著减少（均P<005）。P2组在安静时、运动后即刻及运动后1 h，均较P1组相同时间点的HSP70mRNA显著下降（均P<005）。P1组、P2组力竭运动中通气阈时通气量VE较C组均显著增加(P<005)，且受试者血液白细胞HSP70mRNA表达与血清SOD/MDA比例呈显著正相关（R=048，P<005）。结论：一次及多次高温预处理可上调运动后人血液白细胞HSP70mRNA表达，抑制力竭运动所造成的氧化应激损伤。且多次高温预处理后HSP70mRNA表达降低，可能是对高温重复应激的适应性反应 |
| 关键词: 高温预处理 HSP70mRNA 氧自由基 抗氧化酶 递增负荷运动 力竭 |
| DOI： |
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| 基金项目: |
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| Effects of Hyperthermic Preconditioning on Blood Leucocyte HSP70mRNA and Oxygen Free Radical after Exhaustive Exercise |
| CHEN Ting |
| (School of Physical Education, Tibet University for Nationalities) |
| Abstract: |
| Objectives: To discuss the effects of two kinds of hyperthermic preconditioning on blood leucocyte HSP70mRNA and oxygen free radical after incremental exercise. Methods: The subjects are randomly divided into 3 groups: exercise control group(C) ,exercise after one hyperthermic preconditioning group(P1), and exercise after more hyperthermic preconditioning group(P2). P1 Group: The hyperthermic preconditioning is performed for an hour(Sauna, 46±1℃; relative humidity, 85%90%). P2 Group: one hyperthermic preconditioning every three days, total eight times are performed. Group C applies Bruce protocol on treadmill to do incremental exercise to exhaustion. P1 and P2 Group are at rest under the normal temperature for 24 hours after hyperthermic preconditioning, and then do incremental exercise to exhaustion on treadmill. The maximum heart rate, maximal exercise ventilation, maximal oxygen uptake, respiration quotient are recorded at the end of the exercise, and the ventilation rate, maximal oxygen uptake utilization ratio are recorded at the same time. The elbow vein blood of C Group, P1 and P2 are collected before exercise, immediately after exercise, and 1 hour after exercise. By RTPCR method, the tested groups’ expression of blood white cells HSP70mRNA are detected, content of malondialdehyde (MDA) in the serum is determined by the method of TBA and superoxide dismutase (SOD) activity is measured by the method of xanthine oxidase, blood lactic acid values is examined by the blood lactate analyzer. Results: in C Group, in immediate testing, the expression of HSP70mRNA and the content of serum MDA are significantly increased (P<001, P<005) compared with the test at rest. C Group after 1 hour’s exercise, HSP70mRNA expression and MDA content are significantly reduced compared with immediate testing (both P<005), while the serum SOD activity is significantly decreased (P<005) compared with immediate testing. Compared with C Group, HSP70mRNA expression in P1 Group increases significantly at rest, immediately and 1h after exercise(both P<005). SOD activity of P1 Group elevates significantly immediately after exercise (P<005). Compared with C Group, HSP70mRNA expression and SOD activity in P2 Group increases significantly at immediately and 1hour after exercise (both P<005), MDA content in P2 Group reduces markedly at rest, immediately and1hour after exercise (both P<005). Compared with P1 Group, P2 Group HSP70mRNA expression decreases markedly at rest, immediately after exercise, 1 hour after exercise (P<005). And HSP70mRNA is positively correlated with the production of SOD/MDA(R=048, P<005). Conclusions: Two kinds of hyperthermic preconditioning could increase leukocyte HSP70mRNA expression after incremental exercise, and reduce exhaustive exerciseinduced oxidative damage. Leukocyte HSP70mRNA expression is decreased after one month hyperthermic preconditioning, this may be the adaptive response to repeated heat stress |
| Key words: hyperthermic preconditioning HSP70mRNA oxygen free radical superoxide dismutase incremental exercise exhaustion |
