title: Temporal and spatial organization of tyrosine hydroxylase-immunoreactive cell groups in the embryonic brain of an elasmobranch, the lesser-spotted dogfish Scyliorhinus canicula.
abstract: We have studied the development of catecholaminergic (CA) neuronal groups in the brain of the dogfish Scyliorhinus canicula using immunohistochemistry to tyrosine hydroxylase (TH). The earliest TH-immunoreactive (THir) cells were detected in the primordia of the posterior tubercle and suprachiasmatic nuclei (PTN and SCN, respectively) of stage 26 embryos. At stage 28, THir cells were also seen extending between the SCN and the PTN at ventral thalamic levels. At stage 30, some THir cerebrospinal fluid-contacting neurons and migrated THir cells were found in the walls of the posterior recess, and a few weakly THir cells also appeared at the isthmus level (locus coeruleus) and in the caudal rhombencephalic tegmentum. At stage 31, further THir cell groups appeared in the synencephalon and midbrain (ventral tegmental area/substantia nigra, VTA/SN), and the rhombencephalon (viscerosensory and visceromotor columns). At stage 32, the first THir cells appeared in the pallium, the olfactory bulb and the preoptic area. THir cells are seen in the retina from stage 33. The developmental sequence of THir cell groups in dogfish appears to be rather similar to that described for teleosts, apart from the appearance of the VTA/SN and pallial cells, which lack in teleosts.
authors.affiliation: Department of Cell Biology and Ecology, Faculty of Biology, University of Santiago de Compostela, Spain.
authors.forename: Ivan
authors.initials: I
authors.lastname: Carrera
authors.forename: Catalina
authors.initials: C
authors.lastname: Sueiro
authors.forename: Pilar
authors.initials: P
authors.lastname: Molist
authors.forename: Susana
authors.initials: S
authors.lastname: Ferreiro
authors.forename: Fátima
authors.initials: F
authors.lastname: Adrio
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Rodríguez
authors.forename: Ramón
authors.initials: R
authors.lastname: Anadón
authors.forename: Isabel
authors.initials: I
authors.lastname: Rodríguez-Moldes
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology* / Q000196:embryology; D018940:Elasmobranchii / Q000502:physiology*; D004625:Embryo, Nonmammalian; D047108:Embryonic Development; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D007150:Immunohistochemistry / Q000379:methods; D009474:Neurons / Q000201:enzymology*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
chemical_list: D014446:Tyrosine 3-Monooxygenase