Effects of delta opioid antagonists on enkephalin-induced seizures.
We examined the effect of opioid receptor antagonists on the seizure phenomena induced by specific delta opioid receptor agonist [D-Ser2,Leu5] enkephalyl-Thr (DSLET). The experiments have been performed in the anesthetized rats, and the DSLET-induced seizure phenomena were registered by electrocorticogram and electromyogram. It was demonstrated that two selective delta opioid receptor antagonists, ICI 152,129 and ICI 174,864 inhibited DSLET-induced epileptiform ECoG pattern and myoclonic contractions in a dose-related manner. An equimolar concentration of naloxone failed to antagonize the epileptiform effects of DSLET. It is concluded that delta opioid receptor agonist-induced seizure is mediated by delta receptors, since it can be blocked by delta opioid receptor antagonists. Evidently, delta opioid antagonists can be used as a good tool, in order to demonstrate a delta component in the seizure phenomena induced by other endogenous opioid peptides or their derivatives.
D000818:Animals; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives*; D008297:Male; D009292:Narcotic Antagonists / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D051381:Rats; D011957:Receptors, Opioid / Q000187:drug effects*; D012640:Seizures / Q000139:chemically induced*
D009292:Narcotic Antagonists; D009842:Oligopeptides; D011957:Receptors, Opioid; D004743:Enkephalin, Leucine; C034318:enkephalin, Ser(2), Leu(5), Thr(6)-