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一次力竭性离心运动后大鼠骨骼肌α-actin代谢、α-actin和MHC基因表达及针刺对其影响

Metabolism of α-actin, Expression of α-actin mRNA and MHC mRNA Induced by Exhaustive Eccentric Exercise in Skeletal Muscles of Rats and Effects of Acupuncture on Them

【作者】 王瑞元

【导师】 冯炜权;

【作者基本信息】 北京体育大学 , 运动人体科学, 2000, 博士

【摘要】 为了研究一次力竭性离心运动后大鼠骨骼肌α-actin代谢变化、α-actin mRNA和MHC mRNA表达及针刺对其影响,将130只成年SD大鼠随机分为安静对照组和运动实验组。运动实验组又分为非针刺组和针刺组。将非针刺组和针刺组根据运动后的不同的取样时间分别分为:运动后即刻组、6小时组、12小时组、24小时组、48小时组和72小时组,共分为12组,每组10只大鼠。动物的体重为205±23.3克。将各组动物分笼饲养,自由饮食。运动组大鼠动物在跑台上以16米/分的速度进行持续性下坡跑至力竭(跑台坡度为-16°)。运动时间为3.5-4.5小时,平均4小时。在一次力竭性离心运动后即刻,对针刺组大鼠进行针刺。安静对照组和非针刺组不进行针刺处理。分别在运动后即刻、6、12、24、48、72小时取血和肌肉样品。用紫外分光度法测定了血清CK、LDH活性,并利用Dnase Ⅰ抑制法测定了大鼠骨骼肌G-actin、F-actin和T-actin的含量,利用定量反转录聚合酶链式反应(QRT-PCR)法测定α-actin和MHC基因表达。 本研究发现,一次力竭性离心运动后大鼠血清CK在运动后即刻达到峰值,然后逐渐下降,运动后48小时,恢复到安静对照组水平。而血清LDH在运动后12小时达到峰值,运动后48小时同样恢复到安静对照组水平。针刺组与非针刺组血清CK、LHD的变化没有显著性差异。但是可以看出,针刺组血清CK、LHD的变化幅度较小。 和安静对照组相比,一次力竭性离心运动后大鼠骨骼肌T-actin没有明显变化;G-actin只在运动后即刻显著低于安静对照组;F-actin在运动后即刻到运动后6小时,高于安静对照组,运动后12-24小时降低到低于安静对照组水平,出现延迟性F-actin解聚加强现象。运动后即刻到运动后6小时,针刺组大鼠骨骼肌F-actin的升高幅度低于非针刺组,而在运动后12-24小时显著高于非针刺组。说明针刺对大负荷运动后大鼠骨骼肌F-actin的含量有调节作用。而且,这种调节作用可能是双向的。针刺可以阻遏大负荷运动引起的F-actin延迟性解聚加强。 一次力竭性离心运动后大鼠骨骼肌α-actin的基因表达明显下降,其恢复过程大于72小时。针刺有可能促进运动后α-actin基因表达的恢复。/ 一次力竭性离心运动后大鼠骨骼肌总 MHC基因表达在运动后 6* 小时低于安静对照 组,运动后48小时出现超量基因表达。运动后针刺组总MHC基因表达的变化曲线与非针刺 组相似,但针刺组恢复时限提前,超量基因表达提前,而且超量基因表达的幅度大于非针刺 组。说明针刺可以促进大负荷运动后骨骼肌MHC基因表达的恢复。 运动后MHC各同功型的基因表达可能与运动强度、持续时间、运动形式以及肌纤维在 运动参与工作的情况有关。有可能在基因表达水平上,运动负荷越大,参与工作程度越大的 >肌纤维,运动后恢复期基因的超量表达就越明显。 在针刺的作用下,运动后不同同功型MHC基因表达的变化趋势是:MHC-IIb基因表达 下降,MHC-IIx基因表达增加,MHC·IIa基因表达增加,MHCI基因表达下降。

【Abstract】 The purpose of this study is to investigate the changes of a-actin metabolism, a-actin mRNA and MHC isoform mRNA expression in skeletal muscles of rats after one exhaustive eccentric exercise and the effects of acupuncture on them. 130 adult male SD rats were randomly divided into the sedentary group and the exercise group. The rats of the exercise group were again divided into the acupuncture group and non-acupuncture group. According to the sampling time, the exercise group (the acupuncture and non-acupuncture group) was divided into 12 groups, that is the 0 hours, 6 hours, 12 hours, 24 hours, 48 hours and 72 hours groups. In each group there were ten rats. The rats weighting 205 ± 23.3 (mean ± SE) were maintained at 23 ±1 ℃. They were fed in different chests taking food and drink freely. The rats of the exercise group carried out continuous downhill running with the speed of 16m/min for about 4 hours until exhaustion on the animal treadmill (degree -16?). The rats of the acupuncture group were treated with acupuncture immediately after exhaustive eccentric exercise, but those of the sedentary group and the non-acupuncture group were treated without acupuncture. They were the control groups. The blood and muscle samples were taken immediately, 6 hours, 12 hours, 24 hours, 48 hours and 72 hours after exercise. The serum CK and LDH enzyme activities were measured by means of ultraviolet spectroscopy and the contents of G-actin, F-actin and T-actin in skeletal muscles of rats were measured by means of Dnase I assay. The gene expression of a-actin mRNA and MHC isoforms mRNA were determined by using the quantitative reverse transcription PCR technology.It was found in this study that the serum CK reached the peak immediately after exercise, then gradually decreased to the baseline level 48 hours after exercise. But the serum LDH did not reach the peak until 12 hours after exercise and decreased to the baseline 48 hours after exercise as well. There was no significant difference of the changes of serum CK and LDH between the acupuncture groups and the non-acupuncture groups. However, it could be found that the range of the changes of CK and LDH in the acupuncture groups was smaller than that in the non-acupuncture groups.Compared with the sedentary group, there was no remarkable change of T-actin after exercise. The decreased G-actin could be detected only immediately after exercise. The content of F-actin was significantly higher than that of the sedentary group 0-6 hours after exercise, but 12-24 hours afterexercise it decreased to a lower level than that of the sedentary group. A delayed increase of F-actin depolymerization presented after exercise. The F-actin value of the acupuncture group was improved in a lower range than that of the non-acupuncture group 0~6 hours after exercise, but 12-24 hours after exercise it was remarkably higher than those of the non-acupuncture group. It was shown that acupuncture could regulate the F-actin concentration in skeletal muscles of rats after exercise. Furthermore, the regulation might be bilateral. Acupuncture could stop the increase of F-actin delayed depolymerization induced by high loading exercise.The gene expression of a-actin mRNA in skeletal muscles of rats decreased significantly after one exhaustive exercise. The duration of its recovery was longer than 72 hours. It might be that acupuncture accelerated the recovery process of a-actin mRNA expression after exercise.The MHC mRNA expression of the non-acupuncture group was lower than that of the sedentary group 6-12 hours after exercise. There appeared an excess expression of MHC mRNA 48 hours after exercise. The curve of the change of the total MHC mRNA expression in the acupuncture groups was similar to that in the non-acupuncture group. The duration of recovery of the acupuncture group was shorter, the excess expression of MHC mRNA was ahead of time and its range was higher than that in the non-acupuncture group. It was shown that acupuncture could promote the recovery of MHC mRNA expre

  • 【分类号】G804.2
  • 【被引频次】28
  • 【下载频次】775
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