AJP - Endocrinology and Metabolism, Vol 243, Issue 5 365-E369, Copyright © 1982 by American Physiological Society
Central infusion of vasopressin decreased plasma vasopressin concentration in dogs
B. C. Wang, L. Share and J. T. Crofton
The effects of increasing the cerebrospinal fluid (CSF) vasopressin
concentration (CSFADH) by intracerebroventricular infusion of vasopressin
on the plasma vasopressin concentration (PADH) were studied in four groups
of anesthetized dogs. One group received an intracerebroventricular
infusion of artificial CSF (ACSF) alone for 90 min; the other groups were
infused intracerebroventricularly with vasopressin at rates of 10, 20, or
50 microunits/min for 90 min. Arterial blood and CSF samples were taken
just before infusion and at 30-min intervals for 210 min. Vasopressin
infused intracerebroventricularly at 10, 20, and 50 microunits/min resulted
in peak CSFADH of 32.2 +/- 5.3, 82.6 +/- 4.5, and 131.4 +/- 12.5
microunits/ml and reductions in PADH of 32, 47, and 51%, respectively. Only
the latter two responses were significant (P less than 0.5-0.01). Because
the peak increases in CSFADH after intracerebroventricular infusion of
vasopressin ranged from values that were similar to or five times higher
than those seen after severe hemorrhage or intracerebroventricular
hypertonic saline infusion, we suggest that centrally acting vasopressin
may play a physiological role in control of vasopressin secretion.
