CONICET | Buscador de Institutos y Recursos Humanos

Ghrelin (GHRL) is an orexigenic peptide that has been investigated as one of the signals responsible for the reproductiveperformance of mammals under fluctuating metabolic conditions. Central GHRL administration impairs spermatogenesis inmice by regulating the hypothalamic?pituitary?gonadal axis function. In the present study, the hypothalamus role as amediator of GHRL effects on sperm fertilizing capacity and male sexual behavior was evaluated. After 42 days ofhypothalamic GHRL infusion or artificial cerebrospinal fluid, in vitro and in vivo sperm fertilizing capacity, testicularα-tubulin, speriolin gene expression and spermatic α-tubulin protein were evaluated. Hypothalamic expression of genesKiss1, Gpr54 and Gnrh was also studied. The second group of animals was infused with one time only GHRL or artificialcerebrospinal fluid into the hypothalamus to evaluate the effects on sexual behavior. Results demonstrated that chronicGHRL administration to male mice significantly increased the percentages of pre-implantation embryo loss and the numberof post-implantation embryo loss. In relation to the gene expression, our results show a relative decrease of Kiss1, Gpr54and Spatc1. Although no significant differences were observed in the quantitative expression of α-tubulin protein, qualitativechanges in its expression pattern were observed. In addition, a dual effect on sexual behavior was observed: 40% of thetreated animals showed a significant reduction in the number of mounts and intromissions, while a 60% showed asignificant decrease in ejaculation latency vs control animals. In conclusion, our results provide evidence that central GHRLadministration possibly induces failure in embryo development and/or implantation in the females mated with treatedmales, possibly because of a negative effect in the α-tubulin pattern.