title: A developmentally regulated switch in neuronal responsiveness to NCAM and N-cadherin in the rat hippocampus.
abstract: Monolayers of control 3T3 fibroblasts and 3T3 cells expressing transfected NCAM or N-cadherin have been used as a culture substratum for rat hippocampal neurons. Both NCAM and N-cadherin are expressed in the hippocampus through embryonic day 17 (E17) to postnatal day 4 (PND4); however, whereas E17 neurons responded to transfected NCAM by extending considerably longer neurites, PND4 neurons responded very poorly. The converse was true for responsiveness to N-cadherin. These data demonstrate a switch in neuronal responsiveness to NCAM and N-cadherin in the developing hippocampus. NCAM-dependent neurite outgrowth from E17 neurons was largely dependent on the presence of alpha 2-8-linked polysialic acid (PSA) on neuronal NCAM. NCAM-dependent neurite outgrowth could be fully inhibited by pertussis toxin or a combination of L- and N-type calcium channel antagonists thus providing direct evidence concerning the nature of the second messenger pathway activated in primary neurons by cell adhesion molecules (CAMs).
authors.affiliation: Department of Experimental Pathology, UMDS, Guy's Hospital, London, UK.
authors.forename: P
authors.initials: P
authors.lastname: Doherty
authors.forename: S D
authors.initials: SD
authors.lastname: Skaper
authors.forename: S E
authors.initials: SE
authors.lastname: Moore
authors.forename: A
authors.initials: A
authors.lastname: Leon
authors.forename: F S
authors.initials: FS
authors.lastname: Walsh
mesh_terms: D016475:3T3 Cells; D000818:Animals; D015820:Cadherins / Q000502:physiology*; D015816:Cell Adhesion Molecules, Neuronal / Q000502:physiology*; D002478:Cells, Cultured; D006624:Hippocampus / Q000196:embryology*; D051379:Mice; D009474:Neurons / Q000166:cytology / Q000502:physiology; D011134:Polysaccharides / Q000502:physiology; D051381:Rats; D012794:Sialic Acids / Q000502:physiology; D014162:Transfection
chemical_list: D015820:Cadherins; D015816:Cell Adhesion Molecules, Neuronal; D011134:Polysaccharides; D012794:Sialic Acids; C021319:polysialic acid