Nitric oxide inhibits the shedding of the glycosylphosphatidylinositol-anchored dipeptidase from porcine renal proximal tubules.
NO is related to the pathological condition acute renal failure, in which we previously observed that the level of soluble dipeptidase in urine was decreased. In this study the role of NO in the shedding of the glycosylphosphatidylinositol (GPI)-anchored form of renal dipeptidase (RDPase) was examined. The NO donors sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine rapidly inhibited the release of RDPase from porcine kidney proximal tubules. The substrate of NO synthase, l-Arg, also inhibited the release of RDPase, and this effect was reversed by the NO synthase inhibitor N(omega)-nitro-l-arginine methyl ester. Western-blot analyses using antibodies raised against porcine RDPase and the inositol-1,2-cyclic monophosphate moiety formed on phospholipase C cleavage of the GPI anchor demonstrated that SNP mediated its inhibitory effect on the release of RDPase via a GPI-specific phospholipase C (GPI-PLC). Peroxynitrite scavengers (deferoxamine and superoxide dismutase) or reducing agent (dithiothreitol) did not affect SNP's inhibition of the release of RDPase. Exposure to the G-protein activator AlF(-)(4) mimicked the l-Arg effect in the presence of a low concentration of l-Arg, and the effect was completely reversed by U73122, an intracellular phosphatidylinositol-specific PLC (PI-PLC) inhibitor. These results suggest a signal-transduction pathway involving NO, which is produced by NO synthase(s) following activation of a G-protein-coupled PI-PLC, resulting in inhibition of the GPI-PLC that cleaves and releases RDPase. Therefore, this indicates a role for NO as an inhibitory regulator of the shedding of the GPI-anchored RDPase in acute renal failure.
Park
Sung Wook
SW
College of Pharmacy, Chonnam National University, 300 Yongbong-dong, Buk-gu, Kwangju 500-757, Korea.
Yoon
Hyun Joong
HJ
Lee
Hwanghee Blaise
HB
Hooper
Nigel M
NM
Park
Haeng Soon
HS
D000818:Animals; D001120:Arginine / Q000737:chemistry; D015153:Blotting, Western; D003676:Deferoxamine / Q000378:metabolism; D004229:Dithiothreitol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D007684:Kidney Tubules / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009573:Nitrites / Q000378:metabolism; D009599:Nitroprusside / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011485:Protein Binding; D011760:Pyrrolidinones / Q000494:pharmacology; D026423:S-Nitroso-N-Acetylpenicillamine / Q000494:pharmacology; D015398:Signal Transduction; D013482:Superoxide Dismutase / Q000378:metabolism; D013552:Swine; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism
D004791:Enzyme Inhibitors; D004963:Estrenes; D017261:Glycosylphosphatidylinositols; D020030:Nitric Oxide Donors; D009573:Nitrites; D010726:Phosphodiesterase Inhibitors; D011760:Pyrrolidinones; C110881:S-nitro-N-acetylpenicillamine; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D009599:Nitroprusside; D009569:Nitric Oxide; D026423:S-Nitroso-N-Acetylpenicillamine; D001120:Arginine; D013482:Superoxide Dismutase; D010738:Type C Phospholipases; D010396:Penicillamine; D003676:Deferoxamine; D004229:Dithiothreitol; D019331:NG-Nitroarginine Methyl Ester