Identification of luteinizing hormone-releasing hormone (LH-RH) in the brain and pituitary gland of a fish by immunocytochemistry.

For the first time immunoreactive luteinizing hormone-releasing hormone (LH-RH) is demonstrated in both the brain and pituitary gland of a teleost (Xiphophorus maculatus) using an immunoperoxidase procedure. It is specifically localized in the perikarya and their axons of the ventral telencephalon and nucleus lateralis tuberis and within and between the gonadotrops and within some cells of the pars intermedia. These immunoreactions are extinguished when antiserum to LH-RH is preincubated with LH-RH antigen but not with neurohypophysial hormones.