title: Immunohistochemical and ultrastructural evidence of adrenal chromaffin cell subtypes in sea bass Dicentrarchus labrax (L.).
abstract: Histology demonstrated chromaffin cells in the head kidney and opisthonephros of the sea bass. Immunohistochemistry showed the catecholamine-synthesizing enzymes tyrosine hydroxylase and dopamine beta-hydroxylase in these cells. Phenlethanolamine N-methyltransferase was detected in a fraction of the chromaffin cells in the head kidney (59%) and in the opisthonephros (54%). Distinct noradrenaline- and adrenaline-synthesizing cells are therefore suggested. Ultrastructural analysis confirmed the existence of two main chromaffin cell types, distinguished by different types of the secretory granules. Cells that contain vesicles with a round, electron-dense core were interpreted as noradrenaline cells, while cells with electron-lucent vesicles were identified as adrenaline cells. The ultrastructure of these chromaffin cell subtypes does not differ in the head kidney and opisthonephros. A minor population of chromaffin cells was identified, which typically show smaller vesicles with an electron-dense core. This population may account for a limited number of not fully differentiated chromaffin cells.
authors.affiliation: Department of Environmental Sciences, Faculty of Sciences, Tuscia University, Viterbo, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Abelli
authors.forename: V P
authors.initials: VP
authors.lastname: Gallo
authors.forename: A
authors.initials: A
authors.lastname: Civinini
authors.forename: L
authors.initials: L
authors.lastname: Mastrolia
mesh_terms: D000818:Animals; D001492:Bass / Q000033:anatomy & histology / Q000378:metabolism*; D002384:Catalysis; D019439:Chromaffin Cells / Q000737:chemistry* / Q000648:ultrastructure; D004295:Dihydroxyphenylalanine / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D004299:Dopamine beta-Hydroxylase / Q000032:analysis*; D004837:Epinephrine / Q000378:metabolism; D007150:Immunohistochemistry; D007668:Kidney / Q000737:chemistry* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009638:Norepinephrine / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis*
chemical_list: D014443:Tyrosine; D004295:Dihydroxyphenylalanine; D014446:Tyrosine 3-Monooxygenase; D004299:Dopamine beta-Hydroxylase; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine