去卵巢大鼠骨骼肌形态和功能变化研究

Morphological and Functional Changes of Skeletal Muscle in Ovariectomized Rats

目的探讨去卵巢对大鼠骨骼肌形态和功能的影响。方法选取36只6月龄雌性SD大鼠随机分为正常组(不做特殊处理)、假手术组(暴露双侧卵巢仅切除卵巢周围部分脂肪组织)、模型组(切除双侧卵巢),每组12只,室温(25±1)℃,相对湿度(50±10)%,光照黑暗各12h交替下饲养12周。分别在0、6、12周测量大鼠前肢肌力,12周后取材,对各组大鼠股四头肌进行苏木精-伊红(hematoxylin-eosin,HE)染色、油红O染色、Masson染色,观察各组大鼠肌肉组织的形态结构变化,并计算肌纤维横截面积变化。结果在第6、12周,正常组和假手术组大鼠的前肢肌力明显高于模型组,组间比较差异均具有统计学意义(P均<0.05);HE染色、油红O染色、Masson染色显示,与正常组和假手术组相比,模型组大鼠肌纤维排列紊乱,肌纤维间隙增宽伴随大量脂肪沉积,胶原纤维增多,肌纤维横截面积减小;与正常组和假手术组比较,模型组大鼠的股四头肌肌纤维横截面积明显降低,组间比较差异均具有统计学意义(P均<0.05)。结论去卵巢后大鼠的骨骼肌形态和功能会发生明显退变,退变主要表现为肌力下降,骨骼肌中脂肪沉积和胶原纤维增多,肌纤维横截面积减小。

Objective To investigate the effects of ovariectomization on the morphology and function of skeletal muscle in rats.Methods A total of 366-month-old female SD rats were randomly divided into normal group(no special treatment),sham operation group(both ovaries were exposed and only part of the adipose tissue around the ovaries was removed)and model group(both ovaries were removed),with 12 rats in each,room temperature(25±1)C,relative humidity(50±10)%and 12 h of light and dark for 12 weeks.The forelimb muscle strength of rats was measured at 0,6 and 12 weeks respectively,after 12 weeks,the morphological and structural changes of quadriceps femoris muscle of rats in each group were observed by hematoxylin-eosin(HE)staining,oil red O staining and Masson staining,and the changes of muscle cross-sectional area were calculated.Results At week 6 and 12,the forelimb muscle strength of normal group and sham group was significantly higher than that of model group,and the difference was statistically significant(all P<0.05);HE staining,oil red O staining and Masson staining showed that,compared with the normal group and the sham operation group,the arrangement of muscle fibers was disordered,the space between muscle fibers was widened with a large amount of fat deposition,increased collagen fibers and decreased the cross-sectional area of muscle fibers;compared with the normal group and the sham operation group,the cross-sectional area of quadriceps femoris muscle fiber in the model group significantly decreased,and the differences between the groups were statistically significant(all P<0.05).Conclusion The morphological and functional degeneration of skeletal muscle in ovariectomized rats is obvious,and the degeneration is mainly manifested as decreased muscle strength,increased fat deposition and collagen fibers in skeletal muscle,and decreased cross-sectional area of muscle fibers.