一次力竭性离心运动及恢复期间大鼠骨骼肌超微结构及机械生长因子（MGF）的变化

发布时间：2018-03-31 13:08

本文选题：力竭运动　切入点：骨骼肌超微结构　出处：《扬州大学》2012年硕士论文

【摘要】：目的：研究一次力竭性离心运动及恢复期间大鼠骨骼肌超微结构以及机械生长因子MGF的变化情况。方法：实验一：本研究以24只7周左右的健康雄性SD大鼠为研究对象,并随机分为安静对照组(Control)；力竭运动即刻组(E0)；力竭运动后24h组(E24)；力竭运动后48h组(E48)共四组,每组各6只。各力竭运动组进行一次性力竭(下坡跑)运动,在力竭运动后的不同时间点宰杀取样。所有大鼠用乌拉坦腹腔麻醉、宰杀后迅速取股外侧肌、股直肌各一分为二。其中一部分用2.5%戊二醛固定,用于制作电镜超薄切片,在透射电子显微镜下观察骨骼肌超微结构的变化情况,另一部分保存于液氮中冷冻,用于检测大鼠股外侧肌中机械生长因子MGF的情况。实验二：选用4只7周龄成年大鼠和1只新生大鼠,其中成年鼠分组为：安静对照组1只,钝挫伤即刻组1只,钝挫伤24h组1只,钝挫伤48h组1只。采用急性钝挫伤模型,分别于钝挫伤后不同时间点宰杀,迅速取股外侧肌并进行即刻培养。采用倒置相差显微镜随时跟拍每天卫星细胞培养情况。结果： (1)成年大鼠经过一次性力竭离心运动之后,电镜下观察其股直肌的超微结构发现,安静对照组大鼠骨骼肌的超微结构正常。在一次性力竭运动后即刻E0组出现了炎性细胞,间质血管的改变,而力竭运动24小时后即E24组可见骨骼肌细胞、线粒体和内质网均出现扭曲、肿胀等形态改变,Z线、M线明显异常,嵴紊乱等组织学变化情况。 (2)本研究采用酶联免疫吸附法即ELISA检测大鼠血清和骨骼肌中MGF的结果显示,一方面,从血清中MGF的变化情况来看,力竭运动组E0、E24、E48与安静对照组相比呈升高趋势,具有非常显着性差异(P0.01)。另一方面,从骨骼肌中的MGF的变化来看,E0、E24、E48与安静对照组相比,都有升高趋势,其中E24组与安静对照组相比具有非常显着性的差异(P0.01)。 (3)在安静对照组中发现骨骼肌卫星细胞最初呈圆形,多悬浮于培养液中,1天后细胞逐渐贴壁生长,细胞较小,分布均匀,多呈圆形,此后细胞体积逐渐长大,开始分裂,镜下可以看见3-5个或多个细胞成串排列。新生鼠的肌卫星细胞的培养中,与成年大鼠比较,肌卫星细胞的数目较多。肌卫星细胞贴壁培养48小时后开始增殖,肌肉卫星细胞在第5-8天增殖较快,之后增殖减慢。结论： (1)一次性力竭运动后大鼠骨骼肌超微结构出现显著性的组织学变化,例如肌原纤维排列混乱,结构破坏,M线、Z线不够清晰,甚至相邻间断裂,H带、工带界限模糊,细胞内质网线粒体均发生形变,细胞间质水肿明显等现象。 (2)一次性力竭运动及恢复期间,与安静对照组相比,大鼠血清和骨骼肌中机械生长因子(MGF)在力竭后即刻,24小时和48小时呈现增高的趋势,且在24小时后达到峰值,提示MGF可能加快骨骼肌组织和血管再生修复。 (3)大鼠骨骼肌卫星细胞体外培养需要较高的条件要求,钝挫伤后骨骼肌卫星细胞的增殖能力比安静对照组的增殖能力要强。并且新生大鼠卫星细胞的增殖较强。有关大鼠骨骼肌卫星细胞培养的分化条件还有待进一步研究。
[Abstract]:Objective : To study the ultrastructure of skeletal muscle and the changes of mechanical growth factor ( MGF ) in rat skeletal muscle during exercise and recovery .

METHODS : Experiment 1 : Twenty - four healthy male SD rats were randomly divided into two groups : control group ;
exhaustive exercise immediate group ( E0 ) ;
24h after exhaustive exercise ( E24 ) ;
Forty - four groups ( E48 ) were divided into four groups in 48 groups ( E48 ) after exhaustive exercise . All the rats were slaughtered at different time points after exhaustive exercise . All the rats were anesthetized with uranotan , and the rectus muscle and rectus muscle were divided into two groups . One part was fixed with 2.5 % glutaraldehyde . The changes of ultrastructure of skeletal muscle were observed under transmission electron microscope .

Experiment 2 : Four 7 - week - old adult rats and 1 new - born rats were selected . The adult rats were randomly divided into two groups : one in the quiet control group , one in the immediate group in the blunt contusion group , one in the blunt - contusion group and one in the blunt - contusion 48 - hour group .

Results :

( 1 ) The ultrastructure of the rectus muscle was observed under the electron microscope after one - time exhaustive exercise . The changes of inflammatory cells and interstitial vessels were observed in the E24 group immediately after one - time exhaustive exercise .

( 2 ) In this study , the results of MGF in serum and skeletal muscle of rats were determined by enzyme linked immunosorbent assay ( ELISA ) . On the one hand , the levels of E0 , E24 , E48 in exhaustive exercise group were higher than those in the quiet control group ( P0.01 ) .

( 3 ) In the quiet control group , it was found that the skeletal muscle satellite cells were initially round and multi - suspended in the culture medium . After 1 day , the cells grew gradually , the cells were smaller , the distribution was uniform , and the number of cells was more round . After that , the number of muscle satellite cells grew up , and the number of muscle satellite cells began to split . After 48 hours , the muscle satellite cells began to proliferate and the muscle satellite cells grew faster in the 5th - 8 days , and then the proliferation was slowed down .

Conclusion :

( 1 ) There were significant histological changes in the ultrastructure of skeletal muscle of rats after one - time exhaustive exercise , such as confusion of myofibril arrangement , structural damage , M - ray , lack of clarity in Z - line , even adjacent fracture , H - band , blurring of the boundary of the working band , deformation of mitochondria in the endoplasmic reticulum of the cell , and obvious cell - interstitial edema .

( 2 ) During the exercise and recovery of one - time exhaustive exercise , the mechanical growth factor ( MGF ) in serum and skeletal muscle of rats showed an increased tendency immediately after exhaustion , and peaked at 24 hours and 48 hours , and peaked at 24 hours , suggesting that MGF could accelerate the repair of skeletal muscle tissue and vascular regeneration .

( 3 ) In vitro culture of rat skeletal muscle satellite cells requires higher conditions , and the proliferation ability of skeletal muscle satellite cells after blunt trauma is stronger than that in the quiet control group .

【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R873;G804.2

【参考文献】