title: Effects of eight-hour naloxone infusions on human subjects.
abstract: Twelve normal male volunteers received saline control, low-dose naloxone, and high-dose naloxone infusions during three weekly sessions. The sessions were 16 hr long: 1 hr for predrug assessments, 8 hr during which either naloxone or saline was infused in a double-blind procedure, and a 7-hr postdrug observation period. The 8-hr infusions of naloxone had no effect on experimental ischemic arm pain. In addition, the ischemic arm pain procedure did not significantly increase either plasma levels of cortisol or immunoreactive beta-endorphin, suggesting that the procedure was not stressful. The high-dose naloxone infusion resulted in a slightly aversive mood state and prevented the normal circadian decrease in cortisol levels. Both doses of naloxone increased systolic blood pressure and prevented the normal diurnal increase in temperature. The 8-hr infusions of naloxone did not result in changes in pain, mood, or physiological indices beyond what was present within a few hours after starting the infusion.
mesh_terms: D000328:Adult; D000339:Affect / Q000187:drug effects*; D000700:Analgesics; D001288:Attention / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects; D009270:Naloxone / Q000494:pharmacology* / Q000627:therapeutic use; D010146:Pain / Q000517:prevention & control*; D012119:Respiration / Q000187:drug effects; D014851:Wakefulness / Q000187:drug effects
chemical_list: D000700:Analgesics; D009270:Naloxone