IGF-Ⅰ和TGF-β_1在多囊卵巢综合征大鼠卵巢中的表达及意义

Expression and significance of insulin-like growth factor-Ⅰ and transforming growth factor-beta 1 in ovary of rats with polycystic ovary syndrome

目的探讨胰岛素样生长因子-Ⅰ(IGF-Ⅰ)和转化生长因子-β1(TGF-β1)在多囊卵巢综合征(PCOS)发病机制中的作用。方法40只雌性Wistar大鼠随机分为PCOS组和对照组,每组各20只。PCOS组应用来曲唑{1-[双-(4-氰基苯基)甲基]-1,2,4-三氮唑}灌胃制备PCOS大鼠模型,对照组不作任何处理。阴道涂片观察大鼠动情周期变化;运用放免法测定大鼠血清黄体生成素(LH)、卵泡刺激素(FSH)、雌二醇(E2)、孕酮(P)和睾酮(T)水平;光镜观察卵巢、卵泡发育情况;免疫组化法观察卵巢组织中IGF-Ⅰ和TGF-β1的表达。结果PCOS组大鼠失去规律性动情周期变化。血清T、LH浓度高于对照组(P<0.05),血清E2、FSH、P浓度低于对照组(P<0.05)。IGF-Ⅰ在PCOS组颗粒细胞的表达明显强于对照组(P<0.05),TGF-β1在PCOS组卵泡膜细胞和间质细胞的表达明显强于对照组(P<0.05)。结论来曲唑诱导的大鼠动物模型是较好的PCOS模型。IGF-Ⅰ和TGF-β1与PCOS的发病密切相关。

Objective To investigate the role of insulin-like growth factor-Ⅰ （ IGF-Ⅰ ） and transforming growth factor-betal （TGF-β1 ） in the pathogenesis of polycystic ovary syndrome（PCOS）. Methods Forty rats were randomized into two groups：PCOS group（n = 20） and control group（n = 20）. The rats were given letrozole by gavage to induce PCOS in PCOS group,while the rats were not treated in control group. The changes of estrus cycle were observed by means of vaginal smear every day. Gonadal hormone concentrations in serum were determined by radioimmunoassay（RIA）. The development of ovaries and ovarial follicular were observed by light microscope. Using the immunohistochemical staining technique,the expression of IGF-Ⅰ and TGF-β1 was detected. Results The estrus cycles in PCOS group showed an irregular change. Serum levels of testosterone and luteinizing hormone were elevated （ P 〈 0.05 ）, and estradiol, follicle-stimulating hormone and progesterone levels were reduced（P 〈 0.05）. The expression of IGF-Ⅰ in granular cells and TGF-131 in theca cells was significantly higher in PCOS group than in control group （ P 〈 0. 05 ）. Conclusion Letrozole-induced rat model is a better model of PCOS. IGF-Ⅰ and TGF-β1 may be closely correlated with the pathogenesis of PCOS.