Gonadotropin-inhibitory hormone is a hypothalamic peptide that provides a molecular switch between reproduction and feeding

Abstract

Objective: Gonadotropin-inhibitory hormone (GnIH)-3 is a neuropeptide that plays a major role in the regulation of reproduction and feeding in mammals. Materials and Methods: We measured endocrine and behavioural parameters of reproduction in sheep, and sexual behaviour in sheep, mice and cynomolgus monkeys. In addition, GnIH gene expression (in situ hybridization) was examined in ewes, and effects of GnIH-3 on food intake and energy expenditure were measured in various species. GnIH-3 was infused (i.v.) into ewes after an i.m. injection of estradiol benzoate to determine whether the peptide blocks the surge in luteinizing hormone (LH) secretion. Results: GnIH gene expression was reduced in ..