HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 285/4/R770    most recent 00127.2003v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (8) Citing Articles via Google Scholar Google Scholar Articles by Sugiura, S. H. Articles by Ferraris, R. P. Search for Related Content PubMed PubMed Citation Articles by Sugiura, S. H. Articles by Ferraris, R. P.

THIRST AND VOLUME, ELECTROLYTE HOMEOSTASIS

In vivo fractional P_i absorption and NaP_i-II mRNA expression in rainbow trout are upregulated by dietary P restriction

Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103

Submitted 10 March 2003 ; accepted in final form 14 June 2003

Mammalian type II sodium-phosphate cotransporter (NaP_i-II) and inorganic phosphate uptake stimulator (P_iUS) genes are upregulated by dietary phosphorus (P) restriction to increase intestinal and renal P transport, but little is known about NaP_i-II and P_iUS regulation in other vertebrates. We studied the 1) the tissue distribution and dietary regulation of NaP_i-II, P_iUS, and sodium-glucose cotransporter (SGLT1) mRNA and NaP_i-II protein in juvenile rainbow trout (Oncorhynchus mykiss) and 2) effects of dietary P on intestinal P_i absorption in vivo. NaP_i-II, P_iUS, and SGLT1 mRNA were found in the proximal and distal intestine, pyloric ceca, and kidney. P_iUS mRNA was also found in the heart, gill, blood, stomach, liver, skin, and muscle. Tissue distribution of NaP_i-II protein correlated with that of NaP_i-II mRNA except in gill ionocytes where NaP_i-II antibodies recognized related epitopes. Chronic consumption of a low-P diet increased NaP_i-II and P_iUS but not SGLT1 mRNA abundance in the intestine and kidney. Unlike mammals, there was no detectable shift in tissue or cellular localization of NaP_i-II protein in response to dietary P restriction. Regulation of NaP_i and P_iUS mRNA expression was observed only in fish grown under optimal aqueous oxygen concentrations. In vivo fractional absorption of P_i by the intestine decreased in fish fed high-P diets. Decreases in absorption were less pronounced in fish previously fed low-P diets, suggesting that diet history modulates acute regulation of P absorption. Regulation of dietary P_i absorption in vivo may involve a specific change in intestinal NaP_i-II and P_iUS gene expression.

fractional absorption; immunocytochemistry; phosphate uptake stimulator; sodium-glucose cotransporter; sodium-phosphate cotransporter

This article has been cited by other articles:

				F. Yan, R. Angel, and C. M. Ashwell Characterization of the Chicken Small Intestine Type IIb Sodium Phosphate Cotransporter Poult. Sci., January 1, 2007; 86(1): 67 - 76. [Abstract] [Full Text] [PDF]

				X.-L. Cui, A. M. Schlesier, E. L. Fisher, C. Cerqueira, and R. P. Ferraris Fructose-induced increases in neonatal rat intestinal fructose transport involve the PI3-kinase/Akt signaling pathway Am J Physiol Gastrointest Liver Physiol, June 1, 2005; 288(6): G1310 - G1320. [Abstract] [Full Text] [PDF]

				S. H. Sugiura and R. P. Ferraris Dietary phosphorus-responsive genes in the intestine, pyloric ceca, and kidney of rainbow trout Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2004; 287(3): R541 - R550. [Abstract] [Full Text] [PDF]

				X.-L. Cui, P. Soteropoulos, P. Tolias, and R. P. Ferraris Fructose-responsive genes in the small intestine of neonatal rats Physiol Genomics, July 8, 2004; 18(2): 206 - 217. [Abstract] [Full Text] [PDF]