AJP - Regu Watch the video to see how APS reaches out to developing nations.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol 295: R971-R978, 2008. First published July 30, 2008; doi:10.1152/ajpregu.90328.2008
0363-6119/08 $8.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
295/3/R971    most recent
90328.2008v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ivanis, G.
Right arrow Articles by Perry, S. F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ivanis, G.
Right arrow Articles by Perry, S. F.

COMPARATIVE AND EVOLUTIONARY PHYSIOLOGY

Renal expression and localization of SLC9A3 sodium/hydrogen exchanger and its possible role in acid-base regulation in freshwater rainbow trout (Oncorhynchus mykiss)

Goran Ivanis, Marvin Braun, and Steve F. Perry

Department of Biology, University of Ottawa, Ottawa, Ontario, Canada

Submitted 31 March 2008 ; accepted in final form 16 July 2008

Experiments were performed to assess the possible involvement of the Na+/H+ exchanger isoform 3 (NHE3; SLC9A3) in renal acid-base regulation in adult rainbow trout (Oncorhynchus mykiss). NHE3 mRNA was expressed at high levels in the kidney relative to its paralog, NHE2. The results of in situ hybridization demonstrated an abundance of NHE3 mRNA in renal tubules. The combination of immunocytochemistry and histological staining revealed that NHE3 was confined to the apical membrane of proximal tubules, where it was colocalized with the vacuolar-type H+-ATPase. Levels of NHE3 protein (assessed by Western blotting) were increased during hypercapnia, likely as a result of increased transcription, as indicated by increasing levels of NHE3 mRNA (as determined by real-time PCR). Plasma cortisol concentration was increased during hypercapnia, and administration of exogenous cortisol caused a marked increase in NHE3 mRNA and protein. Thus we speculate that the elevation of plasma cortisol during hypercapnia contributes to transcriptional activation of NHE3 that ultimately promotes acid-base regulation by stimulating H+ secretion and HCO3– reabsorption.

sodium/hydrogen exchanger; SLC9; proximal tubule; kidney; cortisol; acidosis; sodium/hydrogen exchange; bicarbonate reabsorption


Address for reprint requests and other correspondence: S. F. Perry, Dept. of Biology, Univ. of Ottawa, 30 Marie Curie, Ottawa, ONT K1N 6N5, Canada (e-mail: sfperry{at}uottawa.ca)






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2008 by the American Physiological Society.