The effects of atrial natriuretic peptide on active avoidance behavior in rats. The role of transmitters.

Different doses of rat atrial natriuretic peptide (rANP1-28) were tested as regards the extinction of active avoidance behavior following its injection into the lateral brain ventricle in rats. ANP delayed extinction of the active avoidance reflex in a dose-dependent manner. When the animals were pretreated with different receptor blockers in doses which themselves had no action on the extinction of active avoidance behavior, the action of ANP on this paradigm was completely blocked by haloperidol and atropine, whereas phenoxybenzamine/propranolol, naloxone, bicuculline and methysergide were ineffective. The data suggest that ANP delays the extinction of active avoidance behavior, and that cholinergic and dopaminergic transmitter systems might be involved in this action.