Tolerance to the effect of morphine on escape from reticular formation stimulation.
D000818:Animals; D004361:Drug Tolerance; D004558:Electric Stimulation; D004924:Escape Reaction / Q000187:drug effects*; D005246:Feedback; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D012154:Reticular Formation / Q000502:physiology*
D009020:Morphine