title: Immunocytochemical localization of a galanin-like peptidergic system in the brain and pituitary of some teleost fish.
abstract: Immunostaining of brain and pituitary sections of teleost fishes (eels, salmonidae, cyprinidae, gourami, sculpin, mullet) with anti porcine galanin (GAL) revealed the presence of immunoreactive (ir) perikarya and a rich network of fibers. Ir-perikarya were located rostrodorsally to the recessus preopticus, and in the posterior tuberal hypothalamus. Ir-fibers were abundant in basal telencephalon and around diencephalic ventricular recesses but never contacted their lumen. Furthermore, they were observed in basal hypothalamus, brainstem and ventral medulla. Ir-fibers passed along corticotropic (ACTH), gonadotropic cells and somatotropes (GH cells) in eel and trout pars distalis, but rarely ended in caudal neurohypophysis. In goldfish pituitary ir-fibers occurred in neural digitations and among different cell types which however did not contain a GAL-like peptide. The relation GAL fibers/GH cells appeared more evident in species with a high growth rate. The other species showed a similar distribution of brain GAL. In eels and trout, ir-perikarya were not observed in areas containing somatostatin, GH- and ACTH-releasing factor, and ACTH-like perikarya, suggesting that GAL did not coexist with these peptides. The widespread distribution of a GAL-like peptide in teleost brain suggests that it could play a role of neurotransmitter and/or neuromodulator and regulate the secretion of adenohypophysial hormone(s).
authors.affiliation: Laboratoire de Physiologie, Institut Océanographique, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Olivereau
authors.forename: J M
authors.initials: JM
authors.lastname: Olivereau
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D001933:Brain Stem / Q000737:chemistry; D003530:Cyprinidae / Q000378:metabolism; D004524:Eels / Q000378:metabolism; D005260:Female; D005399:Fishes / Q000378:metabolism*; D019004:Galanin; D007031:Hypothalamus / Q000737:chemistry; D007150:Immunohistochemistry; D008297:Male; D009479:Neuropeptides / Q000032:analysis* / Q000276:immunology; D010455:Peptides / Q000032:analysis* / Q000276:immunology*; D010902:Pituitary Gland / Q000737:chemistry / Q000294:innervation*; D012487:Salmonidae / Q000378:metabolism; D013194:Staining and Labeling
chemical_list: D009479:Neuropeptides; D010455:Peptides; D019004:Galanin