Hydrogen peroxide stimulates chloride secretion in primary inner medullary collecting duct cells via mPGES-1-derived PGE2.
We investigated the role and mechanism of H2O2 in regulation of NaCl transport in primary inner medullary collecting duct (IMCD) cells. IMCD cells were isolated from wild-type mice and grown onto semipermeable membranes, and short-circuit current (Isc) was determined by Ussing chamber. Exposure of IMCD cells to H2O2 at a range of 100-300 microM caused a rapid increase in Isc in a time- and dose-dependent manner. This increase was almost abolished by the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel inhibitors diphenylamine-2-carboxylic acid (DPC) and CFTR inhibitor-172. In contrast, the magnitude of stimulation was unaffected by the epithelial Na+ channel (ENaC) inhibitor amiloride. The H2O2-induced Cl(-) secretion was significantly inhibited by indomethacin, as well as by microsomal PGE synthase-1 (mPGES-1) deficiency. Like H2O2, PGE2 treatment induced a twofold increase in Isc that was reduced by the protein kinase A (PKA) inhibitors H-89 and KT5720. These data suggest that H2O2 stimulates CFTR Cl(-) channel-mediated Cl(-) secretion through cyclooxygenase- and mPGES-1-dependent release of PGE2 and subsequent activation of PKA.
Soodvilai
Sunhapas
S
Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, 30 N. 1900 E., Rm. 4R312, Salt Lake City, UT 84132, USA.
Jia
Zhanjun
Z
Yang
Tianxin
T
D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002227:Carbazoles / Q000494:pharmacology; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism* / Q000502:physiology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D015232:Dinoprostone / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004553:Electric Conductivity; D004594:Electrophysiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000008:administration & dosage / Q000494:pharmacology*; D007211:Indoles / Q000494:pharmacology; D019746:Intramolecular Oxidoreductases / Q000172:deficiency / Q000378:metabolism*; D007546:Isoquinolines / Q000494:pharmacology; D007679:Kidney Medulla; D007685:Kidney Tubules, Collecting / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D008861:Microsomes / Q000378:metabolism; D016877:Oxidants / Q000008:administration & dosage / Q000494:pharmacology*; D000071876:Prostaglandin-E Synthases; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011758:Pyrroles / Q000494:pharmacology; D012965:Sodium Chloride / Q000378:metabolism; D013449:Sulfonamides / Q000494:pharmacology
D002227:Carbazoles; D002712:Chlorides; D004791:Enzyme Inhibitors; D007211:Indoles; D007546:Isoquinolines; D016877:Oxidants; D047428:Protein Kinase Inhibitors; D011758:Pyrroles; D013449:Sulfonamides; D012965:Sodium Chloride; C057416:KT 5720; D000584:Amiloride; D006861:Hydrogen Peroxide; D017868:Cyclic AMP-Dependent Protein Kinases; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases; C000605865:Ptges protein, mouse; D015232:Dinoprostone; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide