CGRP PREVENTS ELECTROCONVULSIVE SHOCK-INDUCED AMNESIA IN RATS

The effects of calcitonin gene-related peptide (CGRP) on electroconvul sive shock (ECS)-induced amnesia and the possible involvement of neuro transmitters in this action were studied in rats. ECS-induced amnesia was elicited in a passive avoidance paradigm. The possible roles of di fferent transmitters involved in mediating CGRP action were followed b y pretreating the animals with different receptor blockers in doses wh ich themselves could not influence the paradigm. CGRP facilitated lear ning in the passive avoidance paradigm and prevented ECS-induced amnes ia in a dose-dependent manner. Pretreatment with atropine, naloxone, p henoxybenzamine, or propranolol blocked the antiamnesic action of CGRP . Other receptor blockers, such as bicuculline, methysergide, and halo peridol, were ineffective. The results support our previous finding th at CGRP facilitates passive avoidance learning and prevents ECS-induce d amnesia. In the antiamnesic action of CGRP, cholinergic, opiate, and alpha- and beta-adrenergic mediators are involved.