Distribution of tyrosine hydroxylase (TH) and dopamine β-hydroxylase (DBH) immunoreactivity in the central nervous system of two chondrostean fishes (Acipenser baeri and Huso huso)

摘要: To obtain a better understanding of the evolution brain catecholaminergic systems fishes, we have examined distribution catecholamine-synthesizing enzymes in two species sturgeon (Acipenser baeri and Huso huso) using antibodies against tyrosine hydroxylase (TH) dopamine-β-hydroxylase (DBH; only analyzed Acipenser). Both sturgeons showed TH-immunoreactive (THir) neurons widely distributed most regions brain, highest number THir cells being located forebrain (olfactory bulb, preoptic area, posterior tuberculum). were also seen other areas (retrobulbar dorsal ventral telencephalic areas, hypothalamus, thalamus, pretectal area) brainstem (locus coeruleus, viscerosensory caudal reticular formation, area postrema). Immunoreactive fibers varicosities wide distribution, particularly abundant diencephalon mesencephalon. DBH-immunoreactive (DBHir) observed anterior tuberal nucleus, where these TH-negative, locus coeruleus rhombencephalon (vagal formation), DBHir THir. scarce telencephalon very diencephalon, mesencephalon, rhombencephalon. The comparative analysis chondrosteans those groups fishes tetrapods indicate similar organization many nuclei, as well characteristics that are probably primitive, such presence large groups. © 2002 Wiley-Liss, Inc.