Cholinomimetics produce seizures and brain damage in rats

Microinjections of the cholinergic agonists, carbachol and bethanechol, either into the amygdala or into the dorsal hippocampus produced sustained limbic seizures and brain damage in rats. Systemic administration of pilocarpine in rats resulted in a sequence of convulsive disorders and widespread brain damage as well. Scopolamine prevented the development of convulsive activity and brain damage produced by cholinomimetics. These results suggest that the excessive stimulation of cholinergic muscarinic receptors can lead to limbic seizures and brain damage. It is postulated that muscarinic cholinergic mechanisms are linked to the etiology of temporal lobe epilepsy and epileptic brain damage.