Summary
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.
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Sztriha, L., Lelkes, Z., Benedek, G. et al. Potentiating effect of morphine on seizures induced by kainic acid in rats. Naunyn-Schmiedeberg's Arch. Pharmacol. 333, 47–51 (1986). https://doi.org/10.1007/BF00569659
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DOI: https://doi.org/10.1007/BF00569659