外源性雌激素局部应用对去势雌性大鼠颏舌肌肌球蛋白重链基因表达的影响

Effects of exogenous estrogen on the gene expression of genioglossus myosin heavy chain(MHC) in ovariectomized rats

目的:检测外源性雌激素局部应用对去卵巢大鼠颏舌肌肌球蛋白重链(myosin heavy chain,MHC)基因表达的影响,探讨雌激素水平与颏舌肌肌功能的相关性。方法:将30只7周龄健康雌性体质量210g左右的SD大鼠随机分为3组,每组10只。①去卵巢对照组(ovariectomized group,OVX组);②雌激素给药组(E2组);③假手术组(sham-operated group,SO组)。给药30d后取颏舌肌肌肉组织用荧光定量PCR(FQ-PCR)方法检测肌肉组织MHCⅡa、MHCⅡx、MHCⅡb、β-actin(内参照)基因表达。结果:去卵巢对照组颏舌肌MHCⅡb的表达明显高于假手术组(P<0.05),MHCⅡa、MHCⅡx的表达明显低于假手术组(P<0.05)。雌激素给药组颏舌肌MHCⅡb的表达明显低于去卵巢对照组(P<0.01),MHCⅡa、MHCⅡx的表达明显高于去卵巢对照组(P<0.05)。结论:雌激素水平变化能导致颏舌肌肌纤维类型的转化,从而改变肌肉功能。

Objective：To observe the effect of exogenous estrogen on the gene expression of gcnioglossus myosin heavy chain（MHC） gene expression in ovarieetomized rats. Methods： 30 female Sprague-Dawley rats were assigned to three groups randomly ： ovariectomized group （ OVX ）, estrogen group（ E2 ） and sham-operated group （SO）. All the rats were sacrificed at 30 days after injection, and the genioglossus was removed for analysis. The gene expression of MHC Ⅱ a, MHC Ⅱ x, MHC Ⅱ b and β-actin was examined bv real-time quantitative RT-PCR （FQ-PCR）. Results： Compared to the SO group, genioglossus MHC Ⅱb increased significantly in OVX group （P 〈 0.05）, but the expression of MHC Ⅱ a and MHC Ⅱ x decreased significantly （ P 〈 0.05 ）. Compared to the OVX group, genioglossus MHC Ⅱb decreased significantly in estrogen group（ E2 ） （ P 〈 0.05 ） , but the expression of MHC Ⅱ a and MHC Ⅱ x inereased significantly （P 〈0.05）. Conclusion： The change of estrogen level can result in the transformation of geniogtossus muscle fiber type, and accordingly change the muscle function.