title: Differential development of alpha-bungarotoxin-sensitive and alpha-bungarotoxin-insensitive nicotinic acetylcholine receptors in the chick retina.
abstract: The development of cells containing neuronal nicotinic receptors (nAChRs) in the chick retina was investigated by means of immunohistochemical techniques with antibodies directed against the alpha 3 and alpha 8 nAChR subunits. The alpha 3 subunit is one of the major alpha-bungarotoxin-insensitive nicotinic receptor subunits in the chick retina, whereas alpha 8 appears to be the most common alpha-bungarotoxin-sensitive subunit in the same structure, alpha 3-like immunoreactivity (alpha 3-LI) was first detected in cells of the vitreal margin, on the embryonic day 4.5 (E4.5). alpha 8-LI was first detected in the same type of cell almost a day later. However, the processes of alpha 8-LI cells developed much faster than those of alpha 3-LI cells, generating visible stained laminae in the prospective inner plexiform layer as early as E7. alpha 3-LI was only clearly seen in laminae of the inner plexiform layer by E12. By this date, both alpha 3 and alpha 8-LI were seen in the same types of cells as in the adult retina, i.e., amacrines, displaced ganglion cells, and cells of the ganglion cell layer for alpha 3-LI; and amacrines, bipolar cells, and cells of the ganglion cell layer for alpha 8-LI. These results reveal different patterns of development of cells containing the alpha 3 and alpha 8 nAChR subunits in the chick retina and indicate that those nAChR subunits are expressed in the chick retina before choline acetyltransferase-positive cells can be detected and well before synaptogenesis. These data also suggest that nAChRs may have a developmental function in the retina.
authors: Department of Histology and Embryology, University of São Paulo, Brazil.
authors: D E
authors: DE
authors: Hamassaki-Britto
authors: P F
authors: PF
authors: Gardino
authors: J N
authors: JN
authors: Hokoç
authors: K T
authors: KT
authors: Keyser
authors: H J
authors: HJ
authors: Karten
authors: J M
authors: JM
authors: Lindstrom
authors: L R
authors: LR
authors: Britto
mesh_terms: D000818:Animals; D002038:Bungarotoxins / Q000494:pharmacology*; D002642:Chick Embryo; D007124:Immunoenzyme Techniques; D011978:Receptors, Nicotinic / Q000187:drug effects* / Q000378:metabolism; D012160:Retina / Q000737:chemistry* / Q000196:embryology* / Q000254:growth & development
chemical_list: D002038:Bungarotoxins; D011978:Receptors, Nicotinic