Drinking in water deprived rats after combined central angiotensin receptor and converting enzyme blockade

Saralasin, an angiotensin II receptor antagonist, is ineffective in reducing drinking after water-deprivation (WD). Angiotensin III has considerable dipsogenic potency. It may be formed without angiotensin II as an intermediate. To clarify whether angiotensin III formation masks a role for angiotensin in WD, 48 hr WD rats were infused via a lateral cerebroventricle with a) CSF, b) Saralasin, c) SQ 20,881, a converting enzyme inhibitor, or d) Saralasin + SQ. No drug effect on drinking was observed. The results demonstrate that angiotensin III is not required for WD drinking.