Abstract:

The effect of Ghrelin on development of chicken prehierarchical follicles was evaluated in this study. The expression of growth hormone secretagogue receptor (GHSR) was determined by RTPCR, and effects of Ghrelin and follicle stimulating hormone (FSH) on morphology of prehierarchical follicles and laminin and connexin43 labeling indexes in granulosa cells were estimated by histological and immunohistochemical methods. The results showed that GHSR mRNA was expressed in both granulosa and theca layers, and the expression level reached the peak in large white follicle (LWF) and small yellow follicle (SYF), and then decreased thereafter. After treatment with Ghrelin and FSH for 24 h, the thicknesses of granulosa and theca layers and density of granulosa cells were significantly increased in both LWF and SYF in suspension culture (P<0.05). In addition, the labeling indexes of laminin and connexin43 were remarkably elevated in granulosa cells (P<0.05). An additive effect of FSH with ghrelin was demonstrated. In conclusion, the above results indicate that Ghrelin promotes the expression of laminin and connexin43 in granulosa cells to enhance cell to cell interactions, subsequently stimulates the proliferation of granulosa cells, and cooperates with FSH to regulate chicken prehierarchical follicle development.