Modulation of soman-induced neuropathology with an anticonvulsant regimen

Rat hippocampus and piriform cortex were examined for pathological changes 48 hours after exposure to a convulsant dose of soman. Animals were treated with a low dose of atropine just after soman and were then injected, after 10 or 40 minutes of seizures, with both the anticonvulsant drugs NBQX and TCP. Atropine given alone counteracted the extensive neuronal loss due to soman in both areas without prevention of neuronal suffering. Comparatively, the complete anticonvulsant regimen, given before 40 minutes of seizures, totally prevented hippocampal soman-induced neuropathology. Neurones of piriform cortex were still suffering whatever the time of injection of the drugs. This emphasizes the need for a rapid and definitive anticonvulsant treatment just after soman intoxication to block the subsequent neurotoxic effect of nerve-agent exposure.