Immunohistochemical localization of Ghrelin in Testicular Tissues of rooster

Ghrelin has recently emerged as pleiotropic regulator of a wide array of endocrine and non-endocrine functions. The former likely includes the control of gonadal function, as expression of ghrelin and its putative receptor, the GH secretagogue receptor type 1a (GHS-R1a), has been described in mammalian gonads, and direct effects of ghrelin in the control of testicular secretion and cell proliferation have been reported. Yet, the expression and/or functional role of ghrelin in gonads from non-mammalian species remain to be analyzed. This study investigated the immunohistochemical localization of ghrelin in testicular tissues of rooster, using mouse monoclonal anti ghrelin antibody as primary antibody and donkey anti rabbit IgG (HRP) Polyclonal antibody as secondary antibody. Samples of testis collected from five rooster (45 day olds) and for IHC test were kept in 10% Formalin. Then paraffin blocks and histological section for IHC test were prepared.Evaluation of the pattern of cellular expression of ghrelin protein in rooster testis using immunohistochemistry demonstrated that ghrelin peptide was located in the interstitial leydig, sertoli cells and germ cells. Thus, strong ghrelin immunostaining was observed in leydig cells, sertoli cells and germ cells of testicular tissue. No ghrelin signal was detected in control sections. In addition, the sheep testicular tissue was used as positive control Immunoreactions was observed in germ cells, Leydig and Sertoli cells. It is believed that site of ghrelin expression in germ cells, Leydig and Sertoli cells may indicate its role in local regulations. Results of this research are agree with our previous study on Holstein bull, researches on goat and sheep (unpublished data) and some other studies conducted on sheep, cattle and mouse. This is one of the first studies to provide molecular evidence for the presence of ghrelin within the entire testicular tissues of rooster.