|
|
||||||||
AJP - Renal Physiology, Vol 264, Issue 5 833-F836, Copyright © 1993 by American Physiological Society
ARTICLES |
R. H. Sterns, J. Baer, S. Ebersol, D. Thomas, J. W. Lohr and D. E. Kamm
University of Rochester School of Medicine, Department of Medicine, Rochester General Hospital 14621.
The defense of brain volume during hyponatremia cannot be explained by the losses of brain sodium and potassium. We have examined the brain losses of organic osmolytes in rats after 24 h of severe hyponatremia induced by the administration of vasopressin and 5% dextrose in water. Normonatremic controls and animals with intermediate plasma sodium concentration ([Na]) were produced in vasopressin-treated animals by the administration of isocaloric gavages containing varying amounts of NaCl and free water. The animals were killed at 24 h by decapitation, and one brain hemisphere was quickly frozen in liquid nitrogen for organic osmolyte determinations. When compared with controls (plasma [Na] = 139 +/- 1.5 mM), hyponatremic animals (plasma [Na] = 96 +/- 1 mM) had significantly reduced brain contents for sodium, potassium, chloride, glutamate, myo-inositol, N-acetylaspartate, aspartate, creatine, taurine, gamma-aminobutyric acid, and phosphoethanolamine. Plasma [Na] was highly correlated (P < 0.001) with the brain contents for sodium, potassium, and organic osmolytes. Whereas the observed increase in brain water during hyponatremia was only 4.8%, by calculation, brain swelling without brain organic osmolyte losses would have been 11%, an amount that jeopardizes survival.
This article has been cited by other articles:
![]() |
D. L. Shawcross, S. Balata, S. W. M. Olde Damink, P. C. Hayes, J. Wardlaw, I. Marshall, N. E. P. Deutz, R. Williams, and R. Jalan Low myo-inositol and high glutamine levels in brain are associated with neuropsychological deterioration after induced hyperammonemia Am J Physiol Gastrointest Liver Physiol, September 1, 2004; 287(3): G503 - G509. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Silver, B. M. Schroeder, and R. H. Sterns Brain Uptake of Myoinositol after Exogenous Administration J. Am. Soc. Nephrol., May 1, 2002; 13(5): 1255 - 1260. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. LANG, G. L. BUSCH, M. RITTER, H. VOLKL, S. WALDEGGER, E. GULBINS, and D. HAUSSINGER Functional Significance of Cell Volume Regulatory Mechanisms Physiol Rev, January 1, 1998; 78(1): 247 - 306. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |