title: Inhibition of neurite outgrowth in neuroblastoma cells by sphingosine.
abstract: Mouse neuroblastoma NS-20Y cells were induced to grow neurites by removal of serum from the medium. The percentage of cells with neurites reached about 50-60% after 24 h, whereas in medium containing 10% serum only a few cells (1-3%) were bearing neurites. Sphingosine inhibited the neuritogenesis in serum-free medium in a dose-dependent manner; a maximal effect was observed at 1-2 microM. Sphingosine also caused retraction of neurites which had been induced to extend in serum-free medium. N,N-Dimethylsphingosine was 10 times more potent in preventing neurite outgrowth, and N-acetylsphingosine was 10 times less effective compared to sphingosine. However, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7) did not inhibit the extension of neurites. Neurite outgrowth in serum-free medium and its inhibition by sphingosine were still observed in the cells made protein kinase C-deficient by prolonged treatment with phorbol ester. These results suggest that the effect of sphingosine is not mediated by inhibition of protein kinase C.
authors.affiliation: Department of Lipid Biochemistry, Shinshu University School of Medicine, Nagano.
authors.forename: K
authors.initials: K
authors.lastname: Uemura
authors.forename: A
authors.initials: A
authors.lastname: Hara
authors.forename: T
authors.initials: T
authors.lastname: Taketomi
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology*; D001769:Blood; D003470:Culture Media; D007546:Isoquinolines / Q000494:pharmacology; D051379:Mice; D009447:Neuroblastoma / Q000648:ultrastructure*; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D013110:Sphingosine / Q000031:analogs & derivatives / Q000494:pharmacology*; D013552:Swine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D003470:Culture Media; D007546:Isoquinolines; D010879:Piperazines; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C; C061800:N,N-dimethylsphingosine; D013110:Sphingosine; D013755:Tetradecanoylphorbol Acetate