GnIH对卵巢摘除术后补充雌激素大鼠下丘脑POMC阳性神经元的影响

Effects of GnIH on hypothalamic POMC positive neurons in ovariectomized rats supplemented with estrogen

目的:探讨促性腺激素抑制激素(Gn IH/RFRP-3)对卵巢摘除术补充雌激素(OEP)大鼠下丘脑阿片-促黑素细胞皮质素原(POMC)阳性神经元的影响。方法:65只成年雌性SD大鼠,随机选取2只用于免疫荧光多重染色,观察Gn IH/RFRP-3与POMC在大鼠下丘脑神经元的表达;随机选取3只用于免疫共沉淀(Co-IP)实验,检测Gn IH/RFRP-3与POMC的相互作用;余下60只建立卵巢摘除术补充雌激素(OEP)大鼠模型,模型组随机分成注射Gn IH实验组和生理盐水对照组,每组30只,每组根据注射时间不同分为20、40、60、120、240、360min等共6个亚组,每组5只,采用Western Blot法检测Gn IH/RFRP-3处理对下丘脑POMC表达的影响。结果:免疫荧光多重标记结果显示,Gn IH/RFRP-3与POMC共表达于大鼠下丘脑神经元; Co-IP结果证明,Gn IH/RFRP-3与POMC存在相互作用; Western Blot结果表明,注射Gn IH/RFRP-3后20 min组大鼠下丘脑POMC蛋白表达量显著高于对照组(P <0. 05),注射60、120、240、360 min实验组大鼠POMC蛋白表达量明显低于对照组(P <0. 05)。与20 min实验组相比,60、120、240 min组蛋白表达量依次呈下降趋势,360 min组蛋白表达量有升高趋势但是仍然低于20 min组(P <0. 05)。结论:Gn IH/RFRP-3可直接作用于POMC神经元。

Objective:To investigate the effects of gonadotropin inhibitory hormone(GnIH/RFRP-3)on opioid-melanotropic corticotropin(POMC)positive neurons in hypothalamus of ovariectomized rats supplemented with estrogen(OEP).Methods:Sixty-five adult female SD rats were randomly selected two for immunofluorescence multiple staining to observe the expression of GnIH/RFRP-3 and POMC in rat hypothalamic neurons;three Three rats were randomly selected for co-immunoprecipitation(Co-IP)test to detect the interaction between GnIH/RFRP-3 and POMC;the The remaining sixty rats were established as ovariectomy supplementary estrogen(OEP)rat models,and the model group was randomly divided into injection GnIH experiment group and normal saline control group,each Each group was divided into six subgroups,including 20,40,60,120,240,and 360 minutes,and five rats in each group.Western Blot to detect the The effects of GnIH/RFRP-3 treatment on POMC expression in hypothalamus were detected by Western Blot.Results:Immunofluorescence multiple labeling showed that GnIH/RFRP-3 and POMC were co-expressed in rat hypo-thalamic neurons.Co-IP results showed that there is interaction between GnIH/RFRP-3 and POMC.Western Blot results showed that POMC protein expression in hypothalamus of rats in 20 min after GnIH/RFRP-3 injection was significantly higher than that in control group(P<0.05);the The expression of POMC protein in 60,120,240,and 360 min experimental group was significantly lower than that in control group(P<0.05).Compared with the 20 min experimental group,the protein expression in 60,120 and 240 min groups showed a downward trend in turn,the The protein expression in 360 min group showed an upward trend but was still lower than that in 20 min group(P<0.05).Conclusion:GnIH may play a direct role in POMC neurons.