AJP - Renal AJP: Endocrinology and Metabolism
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Renal Physiol 264: F968-F974, 1993;
0363-6127/93 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Adler, S.
Right arrow Articles by Williams, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Adler, S.
Right arrow Articles by Williams, D.

AJP - Renal Physiology, Vol 264, Issue 6 968-F974, Copyright © 1993 by American Physiological Society

ARTICLES

Effect of acute and chronic hyponatremia on brain buffering in rats

S. Adler, J. G. Verbalis and D. Williams
Department of Medicine, Montefiore University, Pittsburgh, Pennsylvania.

The present studies evaluated whether previously observed impairments in brain buffering during acute hyponatremia were maintained during chronic hyponatremia as well and whether the impairment was due in part to changes in brain water, brain perfusion, or activation of arginine vasopressin (AVP) V1 receptors. Acute (1 and 2 day) and chronic (7 and 14 day) hyponatremia was induced in male Sprague-Dawley rats by constant desmopressin administration in combination with a liquid diet. Brain pH was determined by 31P nuclear magnetic resonance (NMR) in rats anesthetized with N2O and paralyzed with pancuronium. Brain buffering was evaluated by the response to CO2 loading, and brain perfusion was evaluated by 19F-NMR using trifluoromethane washout. Compared with normonatremic controls fed the same diet, brain pH in both acute and chronic hyponatremics was 0.12 pH units lower after 55 min ventilation with 20% CO2 despite identical decreases of approximately 0.35 units in all groups during the first 15 min. Moreover, in the recovery period brain pH overshot basal levels only in normonatremic controls. Brain water content in chronic hyponatremic rats was equal to controls, and brain perfusion was identical in the five groups during CO2 exposure. These results are analogous to those reported during acute hyponatremia induced with AVP and show that the impairment of active brain buffering is maintained during chronic hyponatremia and is unrelated to brain water content, perfusion, tissue catabolism, or AVP V1 receptor activation.


This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
S. M. Silver, B. M. Schroeder, P. Bernstein, and R. H. Sterns
Brain adaptation to acute hyponatremia in young rats
Am J Physiol Regulatory Integrative Comp Physiol, June 1, 1999; 276(6): R1595 - R1599.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online