雌激素对慢性间歇性低氧大鼠颏舌肌收缩功能及超微结构的影响  

Effects of estrogen on genioglossus contractile properties and cell ultrastructures in chronic intermittent hypoxia rats

作　　者：齐娟[1] 刘月华[1] 宋纬华[1] 邵校[1] 王飞[1] 

机构地区：[1]同济大学口腔医学院口腔正畸科,200072

出　　处：《实用口腔医学杂志》2008年第2期174-178,共5页Journal of Practical Stomatology

基　　金：国家自然科学基金项目(编号:30572070);上海市科学技术委员会重点基础项目(编号:05JC14057)

摘　　要：目的:探讨雌激素对慢性间歇性低氧大鼠颏舌肌等长收缩功能及肌细胞超微结构的影响。方法:健康雄性SD大鼠40只,随机分为正常对照组(NC)、慢性间歇性低氧组(CIH)、低、中、高剂量雌激素干预组(LE、ME、HE)。后4组建立CIH大鼠模型(8h/d,5周),同时LE、ME、HE组分别予苯甲酸雌二醇0.1、0.2、0.3mg/kg(2次/周)肌肉注射,NC、CIH组予无菌橄榄油0.2ml/次肌肉注射。第5周末电刺激法测定各组大鼠颏舌肌等长收缩功能的变化,透射电镜观察肌细胞超微结构的改变。结果:各组大鼠颏舌肌单刺激收缩、强直收缩最大张力无明显变化;诱导疲劳试验中各时间点颏舌肌抗疲劳性:CIH组显著低于NC组(P<0.01),ME、HE组明显高于CIH组(P<0.05,P<0.01);颏舌肌细胞超微结构:CIH组肌原纤维结构紊乱,部分肌丝溶解、消失,线粒体水肿,嵴断裂,空泡变;ME、HE组肌原纤维病变减轻,部分线粒体水肿,嵴减少。结论:慢性间歇性低氧可破坏大鼠颏舌肌细胞超微结构,降低抗疲劳能力;中、高剂量雌激素可不同程度逆转低氧对肌细胞超微结构及抗疲劳能力的损伤,保护低氧大鼠颏舌肌的抗疲劳能力。Objective：To investigate the effects of estrogen on genioglossus（GG） contractile properties and cell ultrastructures in rats with chronic intermittent hypoxia（CIH）.Methods：Forty male SD rats were randomly divided into five groups：control group（NC）,CIH group,and estrogen group which consist of low dose（LE）,medium dose（ME） and high dose（HE）.Rats in the latter four groups were used to built CIH models（8 h/d,5 weeks）.In the mean time,rats in NC group and CIH group were injected with sterile olive oil,and three estrogen groups were injected with estrogen with doses of 0.1,0.2 and 0.3 mg/kg,twice a week respectively.After five weeks,in vivo isometric contractile properties were investigated,and cell ultrastructural changes in GG were observed under transmission electron microscope.Results：（1） No significant changes of contractile properties were observed among the five groups（P〉0.05）.（2） Compared with NC group,there was a significant decrease in GG fatigue resistance in CIH group（P〈0.01）.While a significant increase in fatigue resistance was observed in ME group and HE group when compared with CIH group（P〈0.05,P〈0.01）.（3） Degenerative morphological findings such as myofibril discontinuities,dilation of mitochondria and disruption of cristae were observed from CIH group,and these degraded ultrastructural changes were partly reversed in ME group and HE group.Conclusion：CIH destroys GG ultrastructures and decreases its endurance properties.Estrogen may protect GG ultrastructures and muscle endurance under hypoxia conditions at certain doses.

关 键 词：雌激素类 缺氧 颏舌肌 收缩能力 

分 类 号：R363[医药卫生—病理学]