不同强度的主动运动对大鼠膝关节软骨的影响

Effects of active exercise of different-intensity on articular cartilage of knee in rats

目的:研究不同强度的主动运动对大鼠膝关节软骨的作用。方法:8周龄雄性SD大鼠40只,随机分为对照组、低强度运动组、中强度运动组、高强度运动组。对照组自由活动,实验组每天按照不同的运动强度进行跑步训练。8周后处死大鼠,切取膝关节关节软骨,以苏木素伊红(HE)及甲苯胺蓝染色、透射电镜等观察不同强度的主动运动对关节软骨形态结构、细胞代谢的影响。结果:运动8周后,低、中强度运动组软骨表面完整,软骨层的厚度较对照组显著增厚(P<0.05);高强度运动组软骨表面部分缺损,表面粗糙,软骨层的厚度较对照组显著降低(P<0.05)。HE染色显示低、中强度运动组软骨负重区蛋白多糖分泌较对照组明显增加,而高强度运动组负重区蛋白多糖分泌较对照组明显减少。透射电镜显示:低、中强度组软骨表面可见明显的圆形突起,膜样胶原纤维连续,而高强度运动组软骨表面圆形突起减少,部分表层胶原纤维暴露。结论:不同强度的主动运动对大鼠膝关节软骨具有不同的作用。低、中强度的主动运动可以增加软骨表面厚度、明显改善关节软骨的代谢,尤以中等强度的作用更明显;高强度的主动运动可能对关节软骨产生破坏效应。

Objective：To research the influences of active exercise of different-intensity on articular cartilage of knee in rats.Method：Forty 8-week-age male SD rats were randomly assigned into one of four groups：non-exercise control group（CG,n=10）,low-intensity exercise group（LG,n=10）,moderate-intensity exercise group（MG,n=10） and high-intensity exercise group（HG,n=10）.The measurement of exercise intensity was referenced with Bedford-plan.After eight weeks exercise,cartilages of rats knee joints were obtained,cartilage sections were stained with hematoxylin and eosin（HE） and toluidine blue and the structure morphology as well as cell metabolism of cartilages were observed under transmission electron microscope.Result：After eight weeks exercise,the cartilage surfaces of LG and MG were integrated,and compared with CG the thickness of cartilage layer increased（P0.05）;the cartilage surfaces of HG were partly defected,damaged and became rough,and compared with CG the thickness of cartilage layer reduced obviously（P0.05）.In HE staining sections,proteoglycan（PG） content in LG and MG was significantly higher than that in CG,while PG content in HG was significantly lower than that in CG.Under transmission of electron microscope,in LG and MG obvious circular tubers on cartilage surfaces,and continuous fibers of collagen were observed;but in HG the circular tubers reduced,and fibers of collagen on surface layer exposed partly.Conclusion：There were different influences of active exercise of different-intensity on articular cartilage of knee in rats.Low and moderate-intensity exercise could increase the thickness of cartilage layer and improve its cell metabolism,especially after moderate-intensity exercise the effects were more obviously.High-intensity exercise might damage the cartilage.