ici-154129 and Epilepsy

Topics: 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; Animals; Digestive System; Enkephalin, Leucine; Enkephalin, Methionine; Epilepsy; Kainic Acid; Male; Mice; Naloxone; Nervous System; Pyrrolidines; Receptors, Opioid

Graded seizure responses to suprathreshold cerebral electroshock in mice were modified by drugs acting at mu- and at delta-opioid receptors. Morphine exerts a proconvulsant effect at a non-mu opioid receptor and may exert a simultaneous anticonvulsant effect at a mu-opioid receptor. Delta-opioid receptor blockade increases seizure severity, suggesting a predominantly anticonvulsant nature of the delta-opioid system in the seizure model tested here.

Topics: Animals; Electric Stimulation; Enkephalin, Leucine; Epilepsy; Mice; Morphine; Naloxone; Narcotic Antagonists; Receptors, Opioid; Receptors, Opioid, delta; Receptors, Opioid, mu; Seizures

In 3 different models of opioid epileptogenesis we have utilized opioid receptor antagonists to differentiate the nature and role of opioid receptor subtypes involved in opioid agonist-induced epileptoid responses in rats. Selective mu-opioid receptor agonism can initiate epileptoid responses in non-dependent rats. Delta-opioid agonism is important in sustaining mu-initiated epileptoid responses. A role for mu-opioid receptor stimulation in delta-opioid initiated epileptoid responses remains yet to be clarified. Delta-opioid antagonism does not precipitate classic autonomic and behavioral signs of withdrawal in morphine-dependent rats but blocks epileptoid responses in naloxone-precipitated morphine withdrawal without affecting autonomic and behavioral components of an ongoing withdrawal reaction.

Topics: Animals; Electroencephalography; Enkephalin, Leucine; Enkephalin, Leucine-2-Alanine; Epilepsy; Male; Morphine; Naloxone; Rats; Rats, Inbred Strains; Receptors, Opioid; Substance Withdrawal Syndrome