Receptor-mediated generation of an EDRF-like intermediate in a neuronal cell line detected by spin trapping techniques.
We have studied receptor-mediated generation of an activator of soluble guanylate cyclase in cultured mouse neuroblastoma cells (clone N1E-115) by ESR/spin trapping spectroscopy. A spin adduct was detected during the activation of muscarinic receptors by carbamylcholine in the presence of the spin trap 3,5-dibromo 4-nitrosobenzene sulphonate (DBNBS). The spin adduct does not correspond to that originating from the free radical nitric oxide or hydroxylamine. The same adduct was generated in cytosol preparations from N1E-115 cells incubated with L-arginine, NADPH, in the presence of calcium. The use of isotopically labelled guanidino-N15-L-arginine supported the generation of a DBNBS spin trapped adduct originating from the guanidino moiety of L-arginine. Superoxide dismutase (SOD) stabilized the precursor of the spin adduct as well as the activator of soluble guanylate cyclase derived from L-arginine. Our results provide direct evidence for the receptor-mediated formation of a diffusible precursor of NO. derived from L-arginine.
Arroyo
C M
CM
Department of Pharmacology and Toxicology, University of Maryland School of Pharmacy, Baltimore 21201.
Forray
C
C
el-Fakahany
E E
EE
Rosen
G M
GM
D000818:Animals; D001120:Arginine / Q000378:metabolism*; D001557:Benzenesulfonates; D002217:Carbachol / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D004789:Enzyme Activation / Q000187:drug effects; D005609:Free Radicals; D006162:Guanylate Cyclase / Q000378:metabolism; D051379:Mice; D009447:Neuroblastoma / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D009589:Nitrogen Oxides / Q000378:metabolism; D009603:Nitroso Compounds; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000378:metabolism*; D013113:Spin Labels; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
D001557:Benzenesulfonates; D005609:Free Radicals; D009589:Nitrogen Oxides; D009603:Nitroso Compounds; D011976:Receptors, Muscarinic; D013113:Spin Labels; D009569:Nitric Oxide; C048757:3,5-dibromo-4-nitrosobenzenesulfonate; D002217:Carbachol; D001120:Arginine; D006162:Guanylate Cyclase