Document Detail


Isoforms and functions of NAD(P)H oxidase at the macula densa.
MedLine Citation:
PMID:  19204183     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Macula densa cells produce superoxide (O2-) during tubuloglomerular feedback primarily via NAD(P)H oxidase (NOX). The purpose of the present study was to determine NOXs expressed by the macula densa and the role of each one in NaCl-induced O2- production. To identify which isoforms are expressed, we applied single-cell RT-PCR to macula densa cells isolated by laser capture microdissection and to MMDD1 cells (a macula densa-like cell line). The captured cells expressed neuronal NOS (marker of macula densa), NOX2, and NOX4 but not NOX1. Expression of the NOXs and neuronal NOS was essentially identical in the MMDD1 cells. Thus, we used MMDD1 cells to investigate which isoform is responsible for NaCl-induced O2- production. We used small-interfering RNA to knock down NOX2 or NOX4 in MMDD1 cells and measured O2- exposed to low-salt solution (LS; 70 mmol/L of NaCl) or high-salt solution (HS; 140 mmol/L of NaCl). Exposing control cells (scrambled small-interfering RNA) to HS increased O2- concentrations from 0.75+/-0.28 to 1.48+/-0.46 U/min per 10(5) cells in LS and HS, respectively (P<0.001). Inhibiting NOX2 blocked the HS-induced increase in O2- (0.62+/-0.39 versus 0.76+/-0.31 U/min per 10(5) cells in LS and HS groups, respectively). Blocking NOX4 did not affect HS-induced O2- levels. O2- levels in the control cells during LS and HS were 0.80+/-0.30 and 1.56+/-0.49 U/min per 10(5) cells, respectively (P<0.001); whereas O2- levels in NOX4-small-interfering RNA-treated cells during LS and HS were 0.40+/-0.25 and 1.26+/-0.51 U/min per 10(5) cells, respectively (P<0.001). We conclude that, whereas macula densa cells express the NOX2 and NOX4 isoforms, NOX2 is primarily responsible for NaCl-induced O2- generation.
Authors:
Rui Zhang; Pamela Harding; Jeffrey L Garvin; Ramiro Juncos; Ed Peterson; Luis A Juncos; Ruisheng Liu
Related Documents :
18845543 - Mechanical induction of an epithelial cell chymase associated with wound edge migration.
3236003 - Resonance raman spectroscopy of hemoglobin in intact cells: a probe of oxygen uptake by...
21947243 - Receptor for advanced glycation end products (rage) partially mediates hmgb1-erks activ...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural     Date:  2009-02-09
Journal Detail:
Title:  Hypertension     Volume:  53     ISSN:  1524-4563     ISO Abbreviation:  Hypertension     Publication Date:  2009 Mar 
Date Detail:
Created Date:  2009-02-20     Completed Date:  2009-03-09     Revised Date:  2011-09-26    
Medline Journal Info:
Nlm Unique ID:  7906255     Medline TA:  Hypertension     Country:  United States    
Other Details:
Languages:  eng     Pagination:  556-63     Citation Subset:  IM    
Affiliation:
Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adenosine / physiology
Animals
Cell Line
Epithelial Cells / cytology,  drug effects,  metabolism
Feedback, Physiological / physiology*
Isoenzymes / metabolism
Kidney Glomerulus / blood supply,  drug effects,  metabolism*
Male
Membrane Glycoproteins / metabolism*
Mice
Microcirculation / drug effects,  physiology
NADPH Oxidase / metabolism*
Oxygen / metabolism
Rats
Rats, Sprague-Dawley
Sodium Chloride / pharmacology
Tumor Necrosis Factor-alpha / metabolism
Grant Support
ID/Acronym/Agency:
R01 DK073401-04/DK/NIDDK NIH HHS; R01 HL086767-02/HL/NHLBI NIH HHS; R01-DK073401/DK/NIDDK NIH HHS; R01-HL086767/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Isoenzymes; 0/Membrane Glycoproteins; 0/Tumor Necrosis Factor-alpha; 58-61-7/Adenosine; 7647-14-5/Sodium Chloride; 7782-44-7/Oxygen; EC 1.6.-/Cybb protein, rat; EC 1.6.-/Nox4 protein, mouse; EC 1.6.-/Nox4 protein, rat; EC 1.6.3.1/Cybb protein, mouse; EC 1.6.3.1/NADPH Oxidase
Comments/Corrections
Comment In:
Hypertension. 2009 Mar;53(3):456-7   [PMID:  19204181 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Immediate and sustained blood pressure lowering by urocortin 2: a novel approach to antihypertensive...
Next Document:  Targeted expression of receptor-associated late transducer inhibits maladaptive hypertrophy via bloc...