Effect of Food Restriction and Weight loss on Ghrelin, Ghrelin Receptor, Aromatase and StAR Gene Expression in Female Rat Ovary

Background and Ghrelin secreted mainly by stomach in food restriction. This neuropeptide is also expressed in ovary. Although effect of weight loss on reproductive system is obvious but the mechanism of this effect is not fully understood. The aim of this study was investigating the effect of minus energy balance on ghrelin، ghrelin receptor، aromatase، and StAR gene expression in different estrus cycle in female rat ovary. In this study 48 intake female wistar rats (250-300g) were divided into two groups. In group 1، rats were 50% food restricted for 10 days. Rats in group 2 were remained intact. In study day، the rats in each group were divided based on their estrous phase (proestrous، estrous، diestrous1 and diestrous2) by vaginal smear test. Rats were anesthetized and their ovaries were isolated. Ghrelin، ghrelin receptor، aromatase and StAR gene expression was assayed by Quantitative Real Time PCR. Quantitative real-time PCR showed that ghrelin and ghrelin receptor mRNA expression in food restricted rats were significantly lower than that of the normal rats but aromatase and StAR mRNA significantly increased in group 1. Our findings indicate that weight loss can have different and independent effect on ovarian ghrelin gene expression.