Location and functional properties of angiotensin targets in the third ventricular region

Centrally mediated effects of angiotensin II (ANG II) in salt and fluid balance of birds were analyzed by: 1. observing physiological responses, 2. identifying putative targets, 3. recording neuronal activity, and compared with corresponding data obtained in mammals. ANG II responsive systems inside and outside the blood-brain-barrier of the hypothalamic region could be characterized in birds as spatially and functionally separate from both central nervous osmoreceptive and neuroendocrine functions in salt and fluid balance. Morphological and functional criteria were consistent in supporting the dual function of ANG II as a physiological systemic messenger to and an intrinsic messenger within the brain.