GONADOTROPIN-RELEASING-HORMONE IN THE MOLLY POECILIA-LATIPINNA - MOLECULAR-FORM, QUANTITY, AND LOCATION

The molecular forms of gonadotropin-releasing hormone (GnRH) present within the brain of the teleost Poecilia latipinna were characterized using high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). The forms present appear to be similar to the previously identified forms of salmon GnRH and chicken GnRH-II. Immunocytochemical studies showed the presence of GnRH-immunoreactive cells in the posterior ventral telencephalon, preoptic area, and midbrain tegmentum. One male fish possessed immunoreactive cells in the nucleus glomerulosus, an area which has not previously been reported to contain GnRH containing cells. GnRH fibers were found extensively throughout the brain, located within the telencephalon, the optic tectum, the hypothalamus, and the midbrain.