AJP - Regulatory, Integrative and Comparative Physiology, Vol 251, Issue 2 333-R340, Copyright © 1986 by American Physiological Society
Peripheral angiotensin II stimulates release of vasotocin in conscious chickens
K. Goto, T. I. Koike, H. L. Neldon and D. W. McKay
In mammals, intracranial or peripheral administration of angiotensin II
(ANG II) has a number of actions, including the release of antidiuretic
hormone (ADH). Relatively little is known of the interactions between the
renin-angiotensin and ADH systems in birds. In the present study [Asp1,
Val5]ANG II (fowl ANG II) was infused intravenously into conscious White
Leghorn cockerels to determine whether peripheral ANG II influences the
release of arginine vasotocin (AVT), the avian ADH. Cannulas were inserted
into a wing artery and vein under local anesthesia. ANG II was dissolved in
0.154 M NaCl and administered intravenously at 0, 2, 20, and 200 ng X kg-1
X min-1. In a second series of experiments, ANG II was infused in 0.1 and
1.0 M NaCl (200 ng X kg-1 X min-1) to examine the effect of the peptide on
osmotic release of ADH. In the three groups administered ANG II in 0.154 M
NaCl, plasma AVT before intravenous infusion averaged between 1.8 +/- 0.46
to 2.6 +/- 0.30 microU/ml. In these birds, infusion of ANG II at 2, 20, and
200 ng X kg-1 X min-1 caused plasma AVT to increase over preinfusion means
by 39, 78, and 300%, respectively. The changes in AVT occurred in the
absence of differences in plasma osmolality, electrolyte composition, or
arterial blood pressure among the groups. In chickens that were
administered ANG II in 0.1 and 1.0 M NaCl, significantly higher plasma AVT
levels were observed compared with a control group receiving the saline
infusions alone.(ABSTRACT TRUNCATED AT 250 WORDS)
