title: Endothelin-stimulated capacitative calcium entry in enteric glial cells: synergistic effects of protein kinase C activity and nitric oxide.
abstract: Depletion of intracellular calcium stores by agonist stimulation is coupled to calcium influx across the plasma membrane, a process termed capacitative calcium entry. Capacitative calcium entry was examined in cultured guinea pig enteric glial cells exposed to endothelin 3. Endothelin 3 (10 nM) caused mobilization of intracellular calcium stores followed by influx of extracellular calcium. This capacitative calcium influx was inhibited by Ni2+ (89 +/- 2%) and by La3+ (78 +/- 2%) but was not affected by L-, N-, or P-type calcium channel blockers. Chelerythrine, a specific antagonist of protein kinase C, dose-dependently inhibited capacitative calcium entry. The nitric oxide synthase inhibitor NG-nitro-L-arginine decreased calcium influx in a dose-dependent manner. The combination of chelerythrine and NG-nitro-L-arginine produced synergistic inhibitory effects. Capacitative calcium entry occurs in enteric glial cells via lanthanum-inhibitable channels through a process regulated by protein kinase C and nitric oxide.
authors.affiliation: Michigan Gastrointestinal Peptide Center, Department of Surgery, University of Michigan, Ann Arbor, USA.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.forename: G A
authors.initials: GA
authors.lastname: Sarosi
authors.forename: D C
authors.initials: DC
authors.lastname: Barnhart
authors.forename: M W
authors.initials: MW
authors.lastname: Mulholland
mesh_terms: D000470:Alkaloids; D000818:Animals; D053119:Benzophenanthridines; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D002273:Carcinogens / Q000494:pharmacology; D002478:Cells, Cultured; D004357:Drug Synergism; D019334:Endothelin-3 / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D009197:Myenteric Plexus / Q000166:cytology; D009457:Neuroglia / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology*; D009532:Nickel / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D019335:Nitroarginine / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives / Q000494:pharmacology; D010617:Phenanthridines / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D019311:Staurosporine / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D019323:omega-N-Methylarginine / Q000494:pharmacology
chemical_list: D000470:Alkaloids; D053119:Benzophenanthridines; D015220:Calcium Channels; D002273:Carcinogens; D019334:Endothelin-3; D004791:Enzyme Inhibitors; D010617:Phenanthridines; C110881:S-nitro-N-acetylpenicillamine; D019335:Nitroarginine; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D009532:Nickel; C016299:chelerythrine; D019001:Nitric Oxide Synthase; D011493:Protein Kinase C; D010396:Penicillamine; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium