Endogenous opioid peptides and epilepsy: quieting the seizing brain?

The brain opioid system has been implicated in the pathophysiology of seizure disorders and cellular mechanisms of epileptogenesis. While opioidpeptides were originally envisioned as endogenous convulsanis, a growing body of evidence demonstrates that these neuropeptides are also anticonvulsant. A role for opioid peptides as neuromodulators of postictalseizure arrest and refractoriness is recognized, and their endogenous activation by seizures is firmly established. Frank Tortella reviews the proconvulsant/anticonvulsant pharmacology of opioid peptides, the evidence for their involvement in postictal mechanisms, and the possible existence in the CNS of an endogenous enticonvulsant substance with opioid peptide-like characteristics.

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