THE ROLE OF ANGIOTENSIN-II IN INGESTIVE BEHAVIOR - A BRIEF REVIEW OF ANGIOTENSIN-II, THIRST AND NA APPETITE

From the outset, the study of angiotensin II (Ang II) in body fluid ho meostasis has been both complicated and intriguing. Since the publicat ion of an early report of the dipsogenic action of this peptide, the p ursuit of the role of Ang II in thirst and Na appetite has continued f or the last 25 years. This pursuit captured the attention of all worke rs interested in the behavioural/physiological regulation of body flui d balance, with major contributions being made by James T. Fitzsimons and his colleagues. In spite of its powerful dipsogenic actions, delin eation of its precise role in physiological thirst has been elusive an d difficult to demonstrate. The influence of Ang II on Na intake took longer to show convincingly. However, in contrast to thirst, the role of Ang II in physiological Na appetite has been demonstrated clearly. The technological advances made during the recent years have greatly i ncreased our ability to delineate the neurobiological context of Ang I I-mediated responses. Thus, the future is promising in regard to illum inating the subtleties of the role of Ang II in body fluid balance.