Tolerance of the facilitatory effect of morphine on self-stimulation of the medial forebrain bundle in rats.
D000818:Animals; D001921:Brain / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D004567:Electrodes, Implanted; D005260:Female; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D012653:Self Stimulation / Q000187:drug effects*; D013238:Stereotaxic Techniques; D013268:Stimulation, Chemical; D013997:Time Factors
D009020:Morphine