title: Chronic stress enhances morphine analgesia in the rat.
mesh_terms: D000698:Analgesia; D000818:Animals; D004597:Electroshock; D006801:Humans; D007276:Injections, Intraventricular; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D009020:Morphine