|
|
||||||||
AJP - Endocrinology and Metabolism, Vol 243, Issue 4 287-E292, Copyright © 1982 by American Physiological Society
ARTICLES |
C. E. Wade, P. Bie, L. C. Keil and D. J. Ramsay
Seven dogs prepared with carotid loops were used to evaluate the responsiveness of the cerebral osmoreceptors regulating plasma vasopressin concentration (pAVP). Intracarotid and intravenous infusions of hypo- and hypertonic solutions were used to alter cerebral plasma osmolality. Bilateral intracarotid infusion of hypertonic saline (0.90 mmol NaCl kg-1 . min-1 . artery-1) significantly elevated jugular vein plasma osmolality (pOsm) in the first minute (P less than 0.05). Systemic values, determined from saphenous vein samples, were increased after 6 min. After 4 min of infusion, systemic pAVP was significantly increased, attaining a constant level at 6 min. Subsequent experiments with infusions 6 min in duration demonstrated that hypertonic saline infused intracarotidly significantly increased pAVP in a dose-related fashion, whereas similar solutions administered intravenously did not alter pAVP. Hypotonic infusions (intravenous or intracarotid) did not change pAVP consistently. The lack of a depression in pAVP during hypotonic infusions is consistent with the argument that jugular pOsm must be elevated above a threshold to stimulate the release of vasopressin. Linear relationships were demonstrated for jugular pNa+ and pOsm to pAVP employing the threshold model. Cerebral osmoreceptors that regulate plasma vasopressin concentration respond linearly to increasing tonicity above a threshold stimulating the release of vasopressin.
This article has been cited by other articles:
![]() |
R. M. Ortiz, C. E. Wade, D. P. Costa, and C. L. Ortiz Renal responses to plasma volume expansion and hyperosmolality in fasting seal pups Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2002; 282(3): R805 - R817. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. C. F. Sandgaard, J. L. Andersen, and P. Bie Hormonal regulation of renal sodium and water excretion during normotensive sodium loading in conscious dogs Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2000; 278(1): R11 - R18. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. H. Carlson and J. W. Osborn Splanchnic and vagal denervation attenuate central Fos but not AVP responses to intragastric salt in rats Am J Physiol Regulatory Integrative Comp Physiol, May 1, 1998; 274(5): R1243 - R1252. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |