Electroconvulsive shock and brain muscarinic receptors: relationship to anterograde amnesia.
Rats were administered one electroconvulsive shock daily for 7 days (ECS X 7) and were killed 24 hours after the last treatment. Muscarinic cholinergic receptor number, as determined by [3H] quinuclidinyl benzilate [( 3H]QNB) binding, was significantly reduced in the cerebral cortex. A parallel group of rats was trained on a passive avoidance task 24 hours following the last ECS and tested for retention of the original avoidance response 24 hours later; these animals exhibited a profound amnesia. Animals tested 1 hour following training were not amnestic, indicating that learning was unimpaired. Animals trained 7 days following ECS X 7 were not amnestic and [3H] QNB binding changes were not demonstrable at this time. A single ECS which does not significantly affect cortical [3H] QNB binding, did not induce amnesia in rats trained 24 hours after the treatment and tested 24 hours later. The parallel, cumulative nature of ECS-induced muscarinic receptor down-regulation and ECS-induced anterograde amnesia suggests a possible causative relationship.
D000647:Amnesia / Q000209:etiology*; D000648:Amnesia, Retrograde / Q000209:etiology*; D000818:Animals; D001921:Brain / Q000502:physiology*; D001923:Brain Chemistry; D002540:Cerebral Cortex / Q000032:analysis; D004565:Electroconvulsive Therapy / Q000009:adverse effects*; D006624:Hippocampus / Q000032:analysis; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D011813:Quinuclidinyl Benzilate / Q000502:physiology; D051381:Rats; D011976:Receptors, Muscarinic / Q000032:analysis / Q000502:physiology*
D011976:Receptors, Muscarinic; D011813:Quinuclidinyl Benzilate