Failure of naloxone to reverse apomorphine effects in humans.
Twelve male volunteers given apomorphine (20 micrograms/kg/hr) for 40 min by i.v. infusion had significant changes in growth hormone, prolactin, vasopressin, pulse rate, sedation and nausea. Naloxone, (20 mg i.v.) or placebo given in a double-blind manner 10 min before the end of the apomorphine infusion as a concealed bolus did not alter the effects of apomorphine. Vasopressin rise correlated significantly with nausea intensity. We conclude that acute opiate receptor blockade does not reverse most apomorphine effects.
D000293:Adolescent; D000328:Adult; D001058:Apomorphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D001127:Arginine Vasopressin / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects; D004347:Drug Interactions; D013006:Growth Hormone / Q000378:metabolism; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D009270:Naloxone / Q000494:pharmacology*; D009325:Nausea / Q000139:chemically induced; D011388:Prolactin / Q000378:metabolism; D011957:Receptors, Opioid / Q000187:drug effects*
D011957:Receptors, Opioid; D001127:Arginine Vasopressin; D009270:Naloxone; D011388:Prolactin; D013006:Growth Hormone; D001058:Apomorphine