AJP - Renal Physiology, Vol 234, Issue 2 135-F140, Copyright © 1978 by American Physiological Society
Localization of central sites of action of angiotensin II on ADH release in vitro
C. M. Gregg and R. L. Malvin
It is now thought that angiotensin II can stimulate antidiuretic hormone
(ADH) release in vivo by a direct action in the central nervous system but
it is not known whether the locus of stimulation is the hypothalamus or the
neurohypophysis or both. Isolated rat neural lobes incubated for 10 min in
buffer containing angiotensin II (200 ng/ml or 2 microgram/ml) did not
increase ADH release compared to control values, but addition of KCl (60
mM) to the bath markedly stimulated ADH release. However, intact
hypothalamoneurohypophysial systems (containing the supraoptic nuclei)
incubated with angiotensin II (200 ng/ml or 2 microgram/ml) did show a
pronounced stimulation of ADH release. The data support the hypothesis that
angiotensin II, at least in vitro, has a central effect on ADH release
which is at the level of the hypothalamus.
