| 2007 JASN IMPACT FACTOR 7.111 | HOME AUTHOR INFO EDITORIAL BOARD SUBSCRIBE FEEDBACK ALERTS HELP | |||
| CURRENT ISSUE | ARCHIVES | JASN Express | ONLINE SUBMISSION | |
Journal of the American Society of Nephrology, Vol 4, 1079-1086, Copyright © 1993 by American Society of Nephrology
REGULAR ARTICLES |
P Pahlavan, LJ Wang, E Sack and JA Arruda
Section of Nephrology, University of Illinois at Chicago 60612.
Chronic respiratory acidosis stimulates the Vmax of the renal brush border Na-H antiporter. The activation of protein kinase C (PKC) by phorbol esters stimulates the activity of the renal Na-H antiporter. In this study, the hypothesis that PKC plays a role in the adaptive increase of the renal brush border Na-H antiporter activity to respiratory acidosis was tested. In vivo respiratory acidosis was associated with an increase in in vitro Na-H antiporter activity and also with an increase in brush border membrane PKC activity, without changes in PKC activity in cytosol or basolateral membranes. Na-H antiporter activity, assessed as the amiloride-sensitive component of 22Na uptake, was measured in cultured proximal tubule cells exposed to 10% CO2 for 48 h. Na-H antiporter activity was significantly higher in cells exposed to 10% CO2 than in those exposed to 5% CO2. To evaluate the role of PKC, cultured cells were depleted of PKC by exposure to the active phorbol ester phorbol 12-myristate 13-acetate (PMA; 10(-7) or 10(-6) M) for 48 h before exposure to 10% CO2. In the presence of 10% CO2, Na-H antiporter activity was significantly lower in PKC-depleted cells than in control. In addition, sphingosine, an inhibitor of PKC, also prevented the adaptation of the Na-H antiporter to 10% CO2 as compared with 5% CO2. In cells treated with the inactive analog 4 alpha- PMA, 22Na uptake was not different than that in control. PMA-treated cells also had a decrease in Na-H antiporter activity during exposure to 5% CO2.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
![]() |
H. Kiwull-Schone, P. Kiwull, S. Frede, and M. Wiemann Role of Brainstem Sodium/Proton Exchanger 3 for Breathing Control during Chronic Acid Base Imbalance Am. J. Respir. Crit. Care Med., September 1, 2007; 176(5): 513 - 519. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Wiemann, S. Frede, D. Bingmann, P. Kiwull, and H. Kiwull-Schone Sodium/Proton Exchanger 3 in the Medulla Oblongata and Set Point of Breathing Control Am. J. Respir. Crit. Care Med., July 15, 2005; 172(2): 244 - 249. [Abstract] [Full Text] [PDF] |
||||
|
HOME
CURRENT ISSUE
ARCHIVES
JASN Express
ONLINE SUBMISSION
AUTHOR INFO
EDITORIAL BOARD SUBSCRIBE FEEDBACK ALERTS HELP |
Copyright © 2008 by the American Society of Nephrology. Online ISSN: 1533-3450 Print ISSN: 1046-6673