Angiotensin and drinking rates in the euryhaline killifish

Abstract

Drinking rates were measured in the euryhaline fish Fundulus heteroclitus in the presence and absence of angiotensin II or its competitive inhibitor P-113 and converting enzyme inhibitor (SQ20881). Angiotensin stimulated drinking in Fundalus adapted to salt- or freshwater. More significant, P-113 decreased drinking rates in saltwater-adapted fish and to ones acutely exposed to saltwater. SQ20881 was also effective in inhibiting drinking. These data are interpreted to support the hypothesis that endogenously produced angiotensin is a physiological stimulus for drinking in fish.