title: Choline acetyltransferase-immunoreactive neurons in the retina of adult and developing lampreys.
abstract: The presence of choline acetyltransferase-immunoreactive (ChATir) amacrine cells is reported for the first time in the retinas of three species of lamprey (Lampetra fluviatilis, Ichthyomyzon unicuspis, and Petromyzon marinus). In the three species, the ChATir cells were mainly distributed in the inner plexiform layer (IPL), which in lampreys extends from the inner nuclear layer (INL) to the inner limiting membrane. These cells had a bipolar, triangular or stellate appearance, and gave rise to processes coursing in the inner plexiform layer. In transforming lampreys, ChATir processes formed two asymmetrical inner and outer subplexuses in the inner plexiform layer, which is reminiscent of the distribution of processes of ChATir cells in the On and Off sublaminae reported in jawed vertebrates. The larval retina lacked ChAT immunoreactivity, and ChATir cells and processes appeared at early metamorphosis throughout the retina, exhibiting in late transforming stages an organization similar to that of adults. This first report of ChATir cells in the lamprey retina indicates that the appearance of cholinergic circuits in the retina of vertebrates occurred before the divergence of the agnathan and gnathostome lines.
authors.affiliation: Department of Functional Biology and Health Sciences, University of Vigo, 36200 Vigo, Spain.
authors.forename: Manuel Angel
authors.initials: MA
authors.lastname: Pombal
authors.forename: Xesús Manoel
authors.initials: XM
authors.lastname: Abalo
authors.forename: María Celina
authors.initials: MC
authors.lastname: Rodicio
authors.forename: Ramón
authors.initials: R
authors.lastname: Anadón
authors.forename: Agustín
authors.initials: A
authors.lastname: González
mesh_terms: D000375:Aging; D000818:Animals; D002452:Cell Count / Q000379:methods; D002795:Choline O-Acetyltransferase / Q000378:metabolism*; D007150:Immunohistochemistry; D007798:Lampreys; D007814:Larva; D009474:Neurons / Q000201:enzymology*; D012160:Retina / Q000166:cytology* / Q000201:enzymology / Q000254:growth & development*; D013045:Species Specificity; D013194:Staining and Labeling
chemical_list: D002795:Choline O-Acetyltransferase