Immunolocalization of the na/h exchanger isoform nhe2 in rat kidney. Chambrey, R[acute]egine, David G. Warnock, Ren[acute]e-Alexandre Podevin, Patrick Bruneval, Chantal Mandet, Marie-France B[acute]elair, Jean Bari[acute]ety, and Michel Paillard. Institut National de la Sant[acute]e et de la Recherche M[acute]edicale Unit[acute]es 356 and 430, Universit[acute]e Pierre et Marie Curie, and H[circumflex]opital Broussais, Paris, France, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-0007.
APStracts 5:0104F, 1998.
Four Na/H exchangers (NHE1 to NHE4) have been detected in the kidney. Renal NHE2 expression sites have not been fully established. We have raised rabbit antisera against an oligopeptide related to the amino acids 652 to 661 of rat NHE2. Western blot analysis of plasma membrane fractions isolated from rat renal cortex showed that affinity purified anti-NHE2 antibody detected an 85 kDa protein in apical, but not in basolateral membranes. The labeling of this 85 kDa protein was specifically blocked by preincubation of the antibody with its monomeric peptide, indicating specific recognition. Indirect immunolabeling was performed on sections of paraformaldehyde-fixed rat kidney embedded in paraffin. Strong staining was seen in the apical membrane of cortical thick ascending limbs, distal convoluted tubules and connecting tubules. Much weaker apical staining was found in medullary thick ascending limbs of Henle. In the inner medulla, some thin limbs were intensively labeled by the anti-NHE2 antibody. No staining could be detected in any segments of the proximal tubule and collecting duct. 

Received 12 January 1998; accepted in final form 29 May 1998.
APS Manuscript Number F10-8.
Article publication pending Am. J. Physiol. (Renal Physiology).
ISSN 1080-4757 Copyright 1998 The American Physiological Society.
Published in APStracts on 16 June 1998