Role of ovarian ghrelin and its receptor in polycystic ovary syndrome pathogenesis

Polycystic ovary syndrome (PCOs) is an endocrine disease that is related to obesity and major metabolic syndromes. Ghrelin is a neuropeptide that plays a key role in metabolism. In this study, we compared the expression of ghrelin and GHS-R mRNA by Quantitative Real-time PCR method in PCOs induced by intramuscular injection of Estradiol valerat (EV) rats versus normal rats in order to determine the role of ghrelin in pathogenesis of PCOs. 48 intake female wistar rats were divided in 2 groups. In group 1, rats received an i.m. injection of 0.4 mg EV in 2 ml oil, 60 days before study day to induce PCOs. Rats in group 2 were remained intact. In study day, rats in each group divided (proestrous, estrous, diestrous1 and diestrous2) by vaginal smear test. Ovaries were isolated then Ghrelin, and ghrelin receptor expressions were assayed by Quantitative Real Time PCR. ghrelin mRNA expression in PCOs rats was significantly lower than normal rats in distrours 1 and 2 but was significantly increased in proestrous and estrus versus normal rats. Also there is no cyclic pattern of Ghrelin expression in rats with PCOs. There is no detectable change in GHS-R1a in normal and PCOs rats.