Expression Analysis ofGnrh1andGnrhr1in Spermatogenic Cells of Rat

Abstract

Hypothalamic Gonadotropin Releasing Hormone (GnRH),viaGnRH receptor (GnRHR), is the main actor in the control of reproduction, in that it induces the biosynthesis and the release of pituitary gonadotropins, which in turn promote steroidogenesis and gametogenesis in both sexes. Extrabrain functions of GnRH have been extensively described in the past decades and, in males, local GnRH activity promotes the progression of spermatogenesis and sperm functions at several levels. The canonical localization ofGnrh1andGnrhr1mRNA is Sertoli and Leydig cells, respectively, but ligand and receptor are also expressed in germ cells. Here, we analysed the expression rate ofGnrh1andGnrhr1in rat testis (180 days old) by quantitative real-time PCR (qPCR) and byin situhybridization we localizedGnrh1andGnrhr1mRNA in different spermatogenic cells of adult animals. Our data confirm the testicular expression ofGnrh1and ofGnrhr1in somatic cells and provide evidence that their expression in the germinal compartment is restricted to haploid cells. In addition, not only Sertoli cells connected to spermatids in the last steps of maturation but also Leydig and peritubular myoid cells expressGnrh1.