title: Ontogeny of cholinergic amacrine cells in the oppossum (Didelphis aurita) retina.
abstract: Immunocytochemistry for choline acetyltransferase (ChAT), the synthesizing enzyme for acetylcholine, was used to determine the onset and to follow the maturation of the cholinergic cells in the retina of a marsupial, the South American opossum (Didelphis aurita). ChAT-immunoreactivity was first detected in amacrine cells in the ganglion cell layer by postnatal day 15 (P15) and in the inner nuclear layer by P35. Much later, at P50 a second sub-population of ChAT-immunoreactive cell bodies was evident in the inner nuclear layer. Processes from ChAT-immunoreactive amacrine cells were detected in the two bands of the inner plexiform layer before synaptogenesis. In the adult retina, these two bands correspond to sublamina 2 and 4 of the inner plexiform layer. In flat whole-mounted preparations, cholinergic cell density was 263 +/- 13 cells/mm2 in the ganglion cell layer and it was estimated a total of 24,000 cholinergic neurons. ChAT-immunoreactive somata showed a random pattern of distribution.
authors.affiliation: Departamento Histologia e Embriologia, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Camargo De Moura Campos
authors.forename: J N
authors.initials: JN
authors.lastname: Hokoç
mesh_terms: D000367:Age Factors; D000818:Animals; D000918:Antibody Specificity; D002452:Cell Count; D002795:Choline O-Acetyltransferase / Q000032:analysis / Q000276:immunology; D002799:Cholinergic Fibers / Q000201:enzymology*; D009893:Opossums / Q000254:growth & development*; D012160:Retina / Q000166:cytology* / Q000201:enzymology / Q000254:growth & development*
chemical_list: D002795:Choline O-Acetyltransferase