Identification of gonadotropin-releasing hormone metabolites in greyhound urine.

Gonadotropin-releasing hormone (GnRH) is a 10-residue peptide hormone that induces secretion of luteinizing hormone (LH) and follicle-stimulating hormone into the blood from the pituitary gland. In males, LH acts on the testes to produce testosterone. The performance-enhancing potential of testosterone makes administration of exogenous GnRH a concern in sports doping control.