|
|
||||||||
2 protein
is increased selectively in renal medulla by chronic hypokalemia
Division of Renal Diseases and Hypertension, Department of Internal Medicine, University of Texas Houston Medical School, Houston, Texas 77030
Our laboratory has demonstrated by Northern analysis that
chronic hypokalemia increases
HK
2 (i.e.,
-subunit of the
colonic H+-K+-ATPase)
mRNA abundance in the rat. To determine whether the increase in mRNA
correlated with an increase in
HK
2 protein, an antibody was
raised against a synthetic peptide derived from amino acids 686-698 of the HK
2
sequence. The anti-HK
2 antibody
hybridized to rat distal colon membranes which migrated at ~100 kDa
(expected mobility of HK
2).
HK
2 protein was not detected in
plasma membranes from rat whole kidney or stomach (100 µg) derived
from control animals. The antibody was then used to investigate changes
in expression of HK
2 in renal
cortex, renal medulla, and distal colon in two pathophysiological
conditions: 1) chronic hypokalemia (LK) and 2) chronic metabolic
acidosis (CMA). In LK rats there was a marked, but selective, increase
in the abundance of HK
2 protein
in membranes prepared from renal medulla. Nevertheless, a corresponding
increase in HK
2 protein
abundance was not observed in membranes prepared from the distal colon
of LK rats. HK
2 protein abundance in CMA was indistinguishable from controls. Moreover, chronic
hypokalemia had no effect on expression of
1-Na+-K+-ATPase
or HK
1 in kidney or distal
colon under any experimental condition. Therefore,
HK
2 protein is tissue- and
site-specifically upregulated in response to chronic hypokalemia but
not by CMA. Furthermore, this regulatory response is localized to the
renal medulla.
proton-potassium-adenosinetriphosphatase; distal colon; acidosis; urinary acidification
This article has been cited by other articles:
![]() |
I. J. Lynch, A. Rudin, S.-L. Xia, L. R. Stow, G. E. Shull, I. D. Weiner, B. D. Cain, and C. S. Wingo Impaired acid secretion in cortical collecting duct intercalated cells from H-K-ATPase-deficient mice: role of HK{alpha} isoforms Am J Physiol Renal Physiol, March 1, 2008; 294(3): F621 - F627. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. B. Pestov, T. V. Korneenko, M. I. Shakhparonov, G. E. Shull, and N. N. Modyanov Loss of acidification of anterior prostate fluids in Atp12a-null mutant mice indicates that nongastric H-K-ATPase functions as proton pump in vivo Am J Physiol Cell Physiol, August 1, 2006; 291(2): C366 - C374. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Codina, J. Li, and T. D. DuBose Jr. CD63 interacts with the carboxy terminus of the colonic H+-K+-ATPase to increase plasma membrane localization and 86Rb+ uptake Am J Physiol Cell Physiol, June 1, 2005; 288(6): C1279 - C1286. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Zhang, X. Xia, L. Zou, X. Xu, G. D. LeSage, and B. C. Kone In vivo expression profile of a H+-K+-ATPase {alpha}2-subunit promoter-reporter transgene Am J Physiol Renal Physiol, June 1, 2004; 286(6): F1171 - F1177. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Spicer, L. L. Clarke, L. R. Gawenis, and G. E. Shull Colonic H+-K+-ATPase in K+ conservation and electrogenic Na+ absorption during Na+ restriction Am J Physiol Gastrointest Liver Physiol, December 1, 2001; 281(6): G1369 - G1377. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Kraut, K. G. Helander, H. F. Helander, N. D. Iroezi, E. A. Marcus, and G. Sachs Detection and localization of H+-K+-ATPase isoforms in human kidney Am J Physiol Renal Physiol, October 1, 2001; 281(4): F763 - F768. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Fejes-Toth and A. Naray-Fejes-Toth Immunohistochemical localization of colonic H-K-ATPase to the apical membrane of connecting tubule cells Am J Physiol Renal Physiol, August 1, 2001; 281(2): F318 - F325. [Abstract] [Full Text] [PDF] |
||||
![]() |
A M Simpson and G J Schwartz Distal renal tubular acidosis with severe hypokalaemia, probably caused by colonic H+-K+-ATPase deficiency Arch. Dis. Child., June 1, 2001; 84(6): 504 - 507. [Abstract] [Full Text] |
||||
![]() |
S. Muto Potassium Transport in the Mammalian Collecting Duct Physiol Rev, January 1, 2001; 81(1): 85 - 116. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Codina, J. Cardwell, J. J. Gitomer, Y. Cui, B. C. Kone, and T. D. Dubose Jr. Sch-28080 depletes intracellular ATP selectively in mIMCD-3 cells Am J Physiol Cell Physiol, November 1, 2000; 279(5): C1319 - C1326. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Codina, T. A. Pressley, and T. D. DuBose Jr. The Colonic H+,K+-ATPase Functions as a Na+-dependent K+(NH4+)-ATPase in Apical Membranes from Rat Distal Colon J. Biol. Chem., July 9, 1999; 274(28): 19693 - 19698. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. B. Pestov, T. V. Korneenko, G. Adams, M. Tillekeratne, M. I. Shakhparonov, and N. N. Modyanov Nongastric H-K-ATPase in rodent prostate: lobe-specific expression and apical localization Am J Physiol Cell Physiol, April 1, 2002; 282(4): C907 - C916. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |