Objective:To investigate the effect of metformin on the level of omentin-1 in serum of rats with polycystic ovary syndrome (PCOS). Methods:Thirty-six rats were divided into three groups:model group, metformin group and control group. HE staining to observe the histopathological changes of ovary, fasting blood glucose (FPG), 1hPG,2hPG, glucose tolerance AUC and serum testosterone (T), progesterone (P), Estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), fasting insulin (FINS), omentin-1 level. Results:In the model group, the follicular membrane cell layer was thickened, the number of granulosa cell layer was decreased, and the luteal tissue was less. In the control group, the granulosa cells in the ovarian tissue were multilayered and multiple luteal bodies were found. The histopathological changes of ovary in metformin group were in between the model group and the control group. The ovarian index, 1hPG, 2hPG and HOMA-IR levels in the model group were significantly higher than those in the control group, and the levels of omentin-1 and serum P,E2,FSH in the model group were significantly lower than those in the control group (P<0.05), and the level of insulin resistance (HOMA-IR) in the steady-state model of FINS was significantly lower than that in the control group. The difference was statistically significant (P<0.05). In metformin group, the ovarian index, serum T,FPG,1hPG,2hPG and FINS,HOMA-IR levels were lower than those in the model group, and the levels of omentin-1 and serum P,T,E2 were significantly higher than those in the model group (P<0.05). Serum omentin-1 was positively correlated with serum P (P<0.05), and negatively correlated with T,FINS,HOMA-IR (P<0.05). Conclusion:Metformin can improve the polycystic ovary syndrome significantly, which provides experimental basis for clinical practice.
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