Bromolysergide and methysergide protection against ECS-induced retrograde amnesia.

Bromolysergide (BOL 148) and methysergide (UML 491), 2 mg/kg intraperitoneally, and saline were administered to rats 45 min before one-trial passive-avoidance conditioning followed by electroconvulsive shock (ECS) or sham-ECS (ECS). On test session (24 h later), the groups treated with both BOL 148 and UML 491 exhibited a clear-cut retention in comparison to saline-ECS rats. On the other hand, all drugged groups, regardless of their submission to ECS, showed a little less pronounced consolidation than saline-ECS rats. The antiamnestic effect brought about by the two drugs was discussed in terms of receptor antagonism against ECS-released brain serotonin, whereas the lower passive-avoidance level observed in treated animals was considered in relation to a possible antipunishment effect of antiserotoninergic treatment.