|
|
||||||||
AJP - Renal Physiology, Vol 264, Issue 5 765-F769, Copyright © 1993 by American Physiological Society
ARTICLES |
R. Mankus, J. H. Schwartz and E. A. Alexander
Thorndike Memorial Laboratory, Boston City Hospital, Massachusetts.
Chronic acid feeding stimulates the rat inner medullary collecting duct (IMCD) to increase acid secretion in vivo (acidification adaptation), but the mechanism for this phenomenon is unknown. Our purpose was to determine whether IMCD cells undergo adaptation in vitro and to explore the mechanism of this response. Confluent cultured rat IMCD cells were exposed to incubation media supplemented with 10(-7) M deoxycorticosterone acetate, pH 7.0 [acid incubated (AI)] or 7.7 [control (C)], for 48 h, and cell pH (pHi) was determined using 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. Resting pHi was 7.46 +/- 0.05 for AI and 7.25 +/- 0.04 for C (P < 0.05). N-ethylmaleimide-sensitive pHi recovery after an acute acid pulse was 0.030 +/- 0.002 for AI and 0.020 +/- 0.002 pH U/min for C (P < 0.05). However, when AI and C cells were incubated with 7 x 10(-6) M cycloheximide, the increment in pHi and enhanced proton pump activity was abolished. In addition, exocytic function, as measured by Lucifer yellow release, was increased significantly in AI cells. In summary, incubation of IMCD cells in acid medium stimulates acidification adaptation by a mechanism dependent on new protein synthesis.
This article has been cited by other articles:
![]() |
G. J. Schwartz, A. M. Kittelberger, R. H. Watkins, and M. A. O'Reilly Carbonic anhydrase XII mRNA encodes a hydratase that is differentially expressed along the rabbit nephron Am J Physiol Renal Physiol, February 1, 2003; 284(2): F399 - F410. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Tsuruoka and G. J. Schwartz Adaptation of the outer medullary collecting duct to metabolic acidosis in vitro Am J Physiol Renal Physiol, December 1, 1998; 275(6): F982 - F990. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. A. Alexander, T. Shih, and J. H. Schwartz H+ secretion is inhibited by clostridial toxins in an inner medullary collecting duct cell line Am J Physiol Renal Physiol, December 1, 1997; 273(6): F1054 - F1057. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |