Nitric oxide decreases cytosolic free calcium in Balb/c 3T3 fibroblasts by a cyclic GMP-independent mechanism.
The purpose of this study was to investigate the effects of NO on cytosolic calcium levels in Balb/c 3T3 fibroblasts that were previously shown to lack soluble guanylate cyclase activity. Authentic NO as well as two NO-generating vasodilators, S-nitroso-N-acetyl-penicillamine and isosorbide dinitrate, decreased cytosolic calcium in these fibroblasts. The effect of NO and S-nitroso-N-acetylpenicillamine was concentration-dependent and, for the most part, reversible. Since S-nitroso-N-acetylpenicillamine did not increase either cGMP or cAMP, NO did not increase cGMP, and 8-bromo-cGMP did not alter cytosolic free calcium, we conclude that NO decreases cytosolic free calcium by a cyclic nucleotide-independent mechanism in Balb/c 3T3 fibroblasts.
Department of Pharmacology, New York Medical College, Valhalla, New York 10595.
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D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D007548:Isosorbide Dinitrate / Q000494:pharmacology*; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000494:pharmacology*; D010396:Penicillamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D026423:S-Nitroso-N-Acetylpenicillamine; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; C016276:8-bromocyclic GMP; D009569:Nitric Oxide; D026423:S-Nitroso-N-Acetylpenicillamine; D000242:Cyclic AMP; D010396:Penicillamine; D006152:Cyclic GMP; D007548:Isosorbide Dinitrate; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine