Chronic stress reduces the analgesic but not the stimulant effect of morphine in mice.
After 10 daily 2-h sessions of immobilization stress, C57BL/6 mice show a reduced response to the analgesic effects of morphine. Chronic stress does not modify the stimulant effect of morphine on locomotor activity. These results are discussed in terms of the effects of stress on different endorphinergic systems.
D000698:Analgesia; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009020:Morphine / Q000008:administration & dosage*; D010146:Pain; D011930:Reaction Time; D013312:Stress, Physiological / Q000378:metabolism*
D009020:Morphine