2007 JASN IMPACT FACTOR 7.111	HOME   AUTHOR INFO   EDITORIAL BOARD   SUBSCRIBE   FEEDBACK   ALERTS   HELP
advanced	CURRENT ISSUE	ARCHIVES	JASN Express	ONLINE SUBMISSION

This Article Full Text Full Text (PDF) 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 PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Stoenoiu, M. S. Articles by Devuyst, O. Search for Related Content PubMed PubMed Citation Articles by Stoenoiu, M. S. Articles by Devuyst, O.

Corticosteroids Induce Expression of Aquaporin-1 and Increase Transcellular Water Transport in Rat Peritoneum

Maria S. Stoenoiu, Jie Ni, Charlotte Verkaeren, Huguette Debaix, Jean-Christophe Jonas^*, Norbert Lameire, Jean-Marc Verbavatz and Olivier Devuyst

Division of Nephrology and *ENDO Unit, Université Catholique de Louvain Medical School, Brussels, Belgium; Division of Nephrology, UZ Ghent, Ghent, Belgium; and Service de Biologie Cellulaire, CEA Saclay, Gif-sur-Yvette, France.

Correpondence to Olivier Devuyst, Division of Nephrology, Université Catholique de Louvain Medical School, 10 Avenue Hippocrate, B-1200 Brussels, Belgium. Phone: 32-2-764-1855; Fax: 32-2-764-5455;

ABSTRACT. The water channel aquaporin-1 (AQP1) is the molecular counterpart of the ultrasmall pore responsible for transcellular water permeability during peritoneal dialysis (PD). This water permeability accounts for up to 50% of ultrafiltration (UF) during a hypertonic dwell, and its loss can be a major clinical problem for PD patients. By analogy with the lung, the hypothesis was tested that corticosteroids may increase AQP1 expression in the peritoneal membrane (PM) and improve water permeability and UF in rats. First, the expression and distribution of the glucocorticoid receptor (GR) in the PM and capillary endothelium was documented. Time-course and dose-response analyses showed that a daily IM injection of dexamethasone (1 or 4 mg/kg) for 5 d induced an approximately twofold increase in the expression of AQP1 at the mRNA and protein levels. The GR antagonist RU-486 completely inhibited the dexamethasone effect. The functional counterpart of the increased AQP1 expression was a significant increase in sodium sieving and net UF across the PM, contrasting with a lack of effect on the osmotic gradient and permeability for small solutes. The latter observation reflected the lack of effect of corticosteroids on nitric oxide synthase (NOS) activity and endothelial NOS isoform expression in the PM. In conclusion, corticosteroids induce AQP1 expression in the capillary endothelium of the PM, which is reflected by increased transcellular water permeability and UF. These data emphasize the critical role of AQP1 during PD and suggest that pharmacologic regulation of AQP1 may provide a target for manipulating water permeability across the PM. E-mail: devuyst@nefr.ucl.ac.be

This article has been cited by other articles:

				H. Belge and O. Devuyst Aquaporin-1--a water channel on the move Nephrol. Dial. Transplant., August 1, 2006; 21(8): 2069 - 2071. [Full Text] [PDF]

				G. Clerbaux, J. Francart, P. Wallemacq, A. Robert, and E. Goffin Evaluation of peritoneal transport properties at onset of peritoneal dialysis and longitudinal follow-up Nephrol. Dial. Transplant., April 1, 2006; 21(4): 1032 - 1039. [Abstract] [Full Text] [PDF]

				A.-S. Martinez, C. P. Cutler, G. D. Wilson, C. Phillips, N. Hazon, and G. Cramb Regulation of expression of two aquaporin homologs in the intestine of the European eel: effects of seawater acclimation and cortisol treatment Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2005; 288(6): R1733 - R1743. [Abstract] [Full Text] [PDF]

				M. Buemi, C. Aloisi, G. Cutroneo, L. Nostro, and A. Favaloro Flowing time on the peritoneal membrane Nephrol. Dial. Transplant., January 1, 2004; 19(1): 26 - 29. [Full Text] [PDF]

				J. Ni, P. Moulin, P. Gianello, O. Feron, J.-L. Balligand, and O. Devuyst Mice that Lack Endothelial Nitric Oxide Synthase Are Protected against Functional and Structural Modifications Induced by Acute Peritonitis J. Am. Soc. Nephrol., December 1, 2003; 14(12): 3205 - 3216. [Abstract] [Full Text] [PDF]

Copyright © 2008 by the American Society of Nephrology. Online ISSN: 1533-3450 Print ISSN: 1046-6673