Dopaminergic influence on the effects of angiotensin II in behavioural reactions

Using a neuropharmacological approach we studied the dopaminergic influence on the effects of angiotensin II (ATII) in some behavioural reactions. Haloperidol reduced the exploratory behaviour-increasing effect of ATII in the open field. Haloperidol also reduced the apomorphine stereotypy-increasing effect of ATII. Sulpiride tended to overcome the locomotor activity-decreasing effect of ATII. Seven resp. 21 days after withdrawal of pimozide (applied for 14 days) the convulsive-seizure thresholdincreasing effect of ATII was enhanced. Haloperidol impaired the retention-facilitating effect of ATII in rats performing a shuttle-box active avoidance task. The results suggest close interactions between central DA-ergic transmission and ATII in the realization of the ATII effects on behaviour.