NEUROANATOMICAL DISTRIBUTION OF ANDROGEN AND ESTROGEN RECEPTOR-IMMUNOREACTIVE CELLS IN THE BRAIN OF THE MALE ROUGHSKIN NEWT

Immunohistochemistry was used to investigate the neuroanatomical distr ibution of androgen and estrogen receptors in brains of adult male rou ghskin newts, Taricha granulosa, collected during the breeding season. Immunoreactive cells were found to be widely distributed in specific brain areas of this urodele amphibian. Androgen receptor-immunoreactiv e (AR-ir) cells were observed in the olfactory bulbs, habenula, pineal body, preoptic area, hypothalamus, interpeduncular nucleus, area acus ticolateralis, cerebellum, and motor nuclei of the medulla oblongata. Estrogen receptor-immunoreactive (ER-ir) cells were found in the later al septum, amygdala pars lateralis, pallium, preoptic area, hypothalam us, and dorsal mesencephalic tegmentum. This immunocytochemical study of the newt brain reveals AR-ir and ER-ir cells in several regions tha t have not been previously reported to contain androgen and estrogen r eceptors in non-mammalian vertebrates. Additionally, the distribution of AR-ir and ER-ir cells in the newt brain, in general, is consistent with previous studies, suggesting that the distribution of sex steroid receptor-containing neurons in some brain regions is relatively conse rved among vertebrates. (C) 1996 Wiley-Liss, Inc.