中文摘要：

本文旨在探讨抗肌营养不良蛋白（dystrophin）和膜通透性在低氧训练中的变化及其作用。8周龄的Sprague Dawley （SD）大鼠共72只,随机分为4组：常氧安静（normoxic non-train, NC）组、常氧运动（normoxic train, NT）组、低氧安静 （hypoxic non-train, HC）组、低氧运动（hypoxic train, HT）组;每组又随机分为3个亚组：无力竭亚组、低速力竭亚组和高速力竭亚组。常氧运动组和低氧运动组进行4周运动训练;低氧组在氧浓度为12.7% （相当于海拔高度4 300 m）的常压低氧环境下生活训练。训练4周后,对各组的无力竭亚组取材,分别测定腓肠肌组织的乳酸脱氢酶（LDH）、琥珀酸脱氢酶（SDH）、苹果酸脱氢酶（MDH）活性和dystrophin含量以及血清LDH活性。其余大鼠分别进行力竭测验,记录力竭时间。结果显示,相对常氧运动组,低氧运动组大鼠体重增长减缓,而骨骼肌dystrophin水平无显著变化。低氧运动对MDH和LDH活性的作用明显。氧浓度和运动训练及其交互作用对MDH均有显著性影响（P〈0.05）,腓肠肌LDH仅受氧浓度的影响（P〈0.05）,而血LDH受氧浓度和运动训练交互作用的影响（P〈0.05）,表现为肌LDH活性下降,血清LDH活性增高。对于大鼠力竭时间,力竭测验速度、运动训练及其交互作用有显著影响（P〈0.05）,运动训练和氧浓度的交互作用也有显著影响（P〈0.05）,而氧浓度的作用没有显著影响。低氧运动组的高速力竭亚组力竭总时间大于常氧运动组的高速力竭亚组,而且在力竭测试中疲劳出现较早但恢复迅速。以上结果提示,低氧运动能够有效延长大鼠高速力竭运动的时间,其作用机制可能与低氧运动后膜通透性增加而引起的血LDH含量上升有关。

英文摘要：

The aim of the present study was to explore the changes and roles of dystrophin and membrane permeability in hypoxic training. Seventy-two 8-week-old Sprague Dawley （SD） rats were randomly divided into 4 groups, normoxic non-train （NC）, normoxic train （NT）, hypoxic non-train （HC）, and hypoxic train （HT） groups. The rats of each group were randomly divided into three subgroups, non-exhaustive, low-speed exhaustive test and high-speed exhaustive test subgroups. Rats in hypoxia groups lived and were trained in a condition of 12.7% oxygen concentration （equal to the 4 300 m altitude）. NT and HT groups received 4 weeks of training exercise. Then the rats in all non-exhaustive subgroups were sacrificed, and gastrocnemii were sampled for the measurements of lactate dehydrogenase （LDH）, succinatedehydrogenase （SDH）, malate dehydrogenase （MDH） activities. Moreover, serum LDH activity was analyzed. Low-speed exhaustive test and high-speed exhaustive test subgroups received exhaustive tests with 20 （71% VO2max） and 30 m/min speed （86% VO2max）, respectively, and their exhaustive times were recorded. The results showed that, compared with normoxic groups, the weights in hypoxia groups exhibited slower increase. The level of dystrophin in HT group without exhaustion test didn＇t change significantly. The muscle MDH activities were markedly affected by the different oxygen concentration, training and their interaction （P 〈 0.05）, whereas the muscle LDH activities were only affected by the different oxygen concentration （P 〈 0.05）. Serum LDH activities were affected by the interaction of the different oxygen concentration and training （P 〈 0.05）, showing decreased muscle LDH and increased blood LDH activities. The exhaustion time were markedly affected by the different test speed, training and their interaction （P 〈 0.05）, and also affected by the interaction of the different oxygen concentration and training （P 〈 0.05）, but didn＇t affected by oxygen co