title: Hydrogen sulfide inhibits activity of three isoforms of recombinant nitric oxide synthase.
abstract: To clarify the presence of cross-talk between H(2)S and NO, we investigated effect of NaHS, an H(2)S donor, on activity of recombinant NO synthase (NOS) isoforms. Activity of all nNOS, iNOS and eNOS was inhibited by NaHS (IC(50): 0.13-0.21 mM). In contrast, Na(2)SO(3), L-cysteine and threo-1,4-dimercapto-2,3-butanediol, a reductant, exerted poor inhibition of NOS activity. Increasing concentrations of tetrahydrobiopterin (BH(4)) reversed the NaHS inhibition of nNOS and eNOS, but not iNOS. Our data thus demonstrate inhibition of three NOS isoforms by NaHS/H(2)S, and suggest involvement of interaction of NaHS/H(2)S with BH(4) in inhibition of nNOS and eNOS, but not iNOS.
authors: Division of Pharmacology and Pathophysiology, Kinki University School of Pharmacy, 3-4-1 Kowakae, Higashi-Osaka 577-8502, Japan.
authors: Satoko
authors: S
authors: Kubo
authors: Yuko
authors: Y
authors: Kurokawa
authors: Ichiko
authors: I
authors: Doe
authors: Takashi
authors: T
authors: Masuko
authors: Fumiko
authors: F
authors: Sekiguchi
authors: Atsufumi
authors: A
authors: Kawabata
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D001708:Biopterins / Q000031:analogs & derivatives / Q000378:metabolism; D003545:Cysteine / Q000633:toxicity; D004229:Dithiothreitol / Q000633:toxicity; D004791:Enzyme Inhibitors; D006801:Humans; D006862:Hydrogen Sulfide / Q000633:toxicity*; D009249:NADP / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I / Q000037:antagonists & inhibitors*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors*; D052250:Nitric Oxide Synthase Type III / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins; D013431:Sulfates / Q000633:toxicity
chemical_list: D000393:Air Pollutants; D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D013431:Sulfates; C012036:sodium sulfate; D001708:Biopterins; D009249:NADP; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C003402:sapropterin; D003545:Cysteine; D004229:Dithiothreitol; D006862:Hydrogen Sulfide