title: Avoidance learning enhanced by post-trial morphine injection.
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D004597:Electroshock; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D011930:Reaction Time / Q000187:drug effects; D013268:Stimulation, Chemical
chemical_list: D009020:Morphine