Volume regulatory action of central angiotensin II in the duck

In the Pekin duck intracerebroventricularly perfused analogues of angiotensin II stimulate the release of neurohypophyseal antidiuretic hormone (AVT) which then acts on the kidneys to reduce glomerular filtration and to increase tubular water permeability. In addition, the centrally mediated inhibition of salt and water excretion via the supraorbital salt glands, as well as vasoconstriction and tachycardia, indicate that angiotensin II plays a major role as a central modulator in the homeostasis of the volume of the extracellular fluid compartment as well as its tonicity.