An inability to antagonize with naloxone the elevated nociceptive thresholds resulting from electrical stimulation of the mesencephalic central gray.
D000818:Animals; D004558:Electric Stimulation; D008297:Male; D008636:Mesencephalon / Q000187:drug effects / Q000502:physiology*; D009270:Naloxone / Q000494:pharmacology*; D010146:Pain / Q000503:physiopathology*; D051381:Rats
D009270:Naloxone