H--k--atpase in rabbit cortical collecting duct b-type intercalated
cell.
Weiner, I. David, and Amy E. Milton.
Division of Nephrology, Hypertension and Transplantation,
University of Florida College of Medicine, Gainesville, FL 32608 and
Gainesville Veterans Administration Medical Center, Gainesville, FL
32608
APStracts 2:0180F, 1995.
The role of H--K--ATPase in the cortical collecting duct (CCD) B-type
intercalated cell (B cell) is unclear. This study examined whether
H--K--ATPase contributes to B cell intracellular pH (pHi) regulation
and, if so, whether it is present at the apical or basolateral
membrane. B cell Na--independent pHi recovery from an acid load was
only partially inhibited by peritubular NEM. Complete inhibition
required combining peritubular NEM either with luminal SCH28080 or
with luminal K--removal. In contrast, neither peritubular SCH28080
nor peritubular K- removal altered pHi regulation. Tomato lectin,
which binds to the gastric H--K--ATPase -subunit, labeled the B cell
apical membrane. We conclude that the rabbit CCD B cell possesses an
apical H--K--ATPase that plays an important role in pHi recovery from
an in vitro acid load.
Received 3 April 1995; accepted in final form 25 September 1995.
APS Manuscript Number F112-5.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 November 95