EFFECT OF DOTARIZINE ON ELECTROCONVULSIVE SHOCK OR PENTYLENETETRAZOL-INDUCED AMNESIA AND ON SEIZURE REACTIVITY IN RATS

Dotarizine (DOT), a compound performing both as calcium antagonist and as 5-HT2 receptor antagonist, was evaluated for its ability to protec t against electroconvulsive shock (ECS)- and pentylenetetrazol (PTZ)-i nduced performance deficit in a passive avoidance ''step-down'' task i n rats. Its effect on electric and PTZ seizure models was also studied . DOT administered orally at a dose of 50 mg/kg for 5 days before lear ning had no significant effect on retention tests given 3 h, 24 h and 7 days after the training session. It should be noted, however; that D OT completely prevented ECS- and PTZ-induced amnesia in passive avoida nce situation. DOT had a pronounced protective effect against electric seizures but did not affect PTZ seizures. The present results provide additional evidence for the role of serotonergic neurotransmitter sys tem and calcium homeostasis for memory and seizure reactivity and may be important in the development of effective treatment strategies for memory dysfunction.