Dynamic Up-regulation of Prodynorphin Transcription in Temporal Lobe Epilepsy

Dynorphin neuropeptides are believed to act as endogenous anticonvulsants, though direct evidence for such a role in humans is sparse. We now report pronounced increases of prodynorphin mRNA expression in the dentate gyrus of patients with temporal lobe epilepsy in comparison to controls. We detected a conspicuously right skewed, bimodal distribution of mRNA levels among patients, suggestive of a dynamic up‐regulation of prodynorphin expression in epilepsy. Highest transcript levels were seen postictally. Our data argue for an essential role of dynorphin in the termination of seizures. © 2009 Wiley‐Liss, Inc.

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