Alteration of dynorphin1-8 and leu-enkephalin in rat hippocampus during seizure and electroacupuncture

Immunocytochemical technics were used to evaluate the influence of penicillin-induced seizure and electroacupuncture treatment on dynorphin1-8 and leu-enkephalin immunoreactivity in hippocampus. It was found that 3 h after beginning of seizure there started a dramatic decrease in dynorphin1-8 in hilus, mossy fiber of hippocampus but an increase in hilus, mossy fiber of hippocampus but an increase in leu-enkephalin in subiculum, CA1 area of hippocampus and some other limbic structures. Electroacupuncture treatment decreased the leu-enkephalin immunoreactivity in the nuclei mentioned above and increased dynorphin1-8 immunoreactivity in hippocampus. The results show that epileptiform activity and electroacupuncture inhibitory effect on seizure may be related to the alteration of dynorphin1-8 and leu-enkephalin in the brain.