ELECTROCORTICOGRAPHIC CHANGES DURING GENERALIZED CONVULSIVE STATUS EPILEPTICUS IN SOMAN INTOXICATED RATS

Generalized convulsive status epilepticus (GCSE) is the most common an d potentially most damaging form of status epilepticus (SE). It has be en previously reported, in both human GCSE and animal models of GCSE, that the electroencephalographs (EEGs) and electrocorticographs (ECoGs ) recorded during GCSE contain an ordered sequence of five identifiabl e patterns: discrete seizures (phase 1), waxing and waning ictal disch arges (phase 2), continuous ictal discharges (phase 3), continuous act ivity with flat periods (phase 4), and periodic epileptiform discharge on a flat background (phase 5). In this paper, we report the same pat tern of ECoG changes in 15 rats exposed to soman, an acetylcholinester ase (AChE) inhibitor. Phase 1 was observed in 12 of 15 animals, but ph ases 2-5 were recorded in all the animals. Taken together, these findi ngs suggest that the sequence of EEG changes is independent of the ini tiating cause, represent a common electrical response to GCSE, and ref lect a common underlying neurochemical mechanism. Published by Elsevie r Science B.V. All rights reserved.