Changes in hippocampal acetylcholine and glutamate extracellular levels during soman-induced seizures: influence of septal cholinoceptive cells.

The changes in extracellular acetylcholine and glutamate levels were determined, during the course of seizures induced by soman, an irreversible inhibitor of acetylcholinesterase, in the CA1 hippocampal area of rats previously injected with atropine or normal saline into septum. The marked increases observed in soman-treated animals were abolished in rats receiving atropine. These data strongly suggest that, during soman intoxication, septal cholinoceptive cells play a key role in controlling the release of acetylcholine and glutamate in hippocampus. The mechanisms underlying this phenomenon are discussed.