Potentiating effect of morphine on seizures induced by kainic acid in rats. An electroencephalographic study.
The effect of morphine pretreatment on kainic acid-induced seizures in rats was investigated by electroencephalographic recording. Seizure activity was quantified by counting the number of spikes in the EEG of freely-moving rats during 2 min periods at 30 min intervals after the intraperitoneal administration of 8, 10 or 12 mg/kg kainic acid. Pretreatment with morphine (1-10 mg/kg s.c.) 10 min before kainic acid administration significantly increased the number of spikes in the EEG in a dose-dependent manner. The potentiating effect of morphine on kainic acid-induced seizures was reduced considerably, but not abolished completely by pretreatment with naloxone (2-5 mg/kg s.c.). The results indicate that the potentiating action of morphine on kainic acid-induced seizures may be exerted in both a specific, naloxone-reversible manner and a non-specific, naloxone-resistant manner.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004569:Electroencephalography; D007608:Kainic Acid / Q000494:pharmacology*; D008297:Male; D009020:Morphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000139:chemically induced*
D009270:Naloxone; D009020:Morphine; D007608:Kainic Acid