Celecoxib as an in vivo probe of cyclooxygenase-2 mechanisms underlying retrograde amnesia in an animal model of ECT

Abstract

Cyclooxygenase-2 (COX-2) mechanisms are involved in glutamate-mediated learning and memory as well as in glutamatergic excitotoxicity. Electroconvulsive therapy (ECT)-induced amnesia may arise from glutamatergic excitotoxicity; if so, COX-2 inhibition may attenuate retrograde amnesia with ECT. Wistar rats which received celecoxib (15 mg/kg per day) or vehicle for 18 days were trained for 3 days on a passive avoidance task. On each of the next 3 days, rats which showed perfect learning (n=51) received true or sham suprathreshold electroconvulsive shocks (ECS; 60 mC) in a factorial design; daily dosing with drug or vehicle was continued. One day after the last ECS, recall of pre-ECS learning was tested. ECS-treated rats showed impaired recall in the vehicle but not celecoxib group. Celecoxib significantly protected against ECS-induced retrograde amnesia; this benefit was independent of the drug-induced attenuation of ECS seizure duration. Celecoxib may protect against ECS-induced retrograde amnesia by attenuating ECS-induced, COX-2-mediated glutamatergic excitotoxicity.