Effect of naloxone on the antipyretic action of acupuncture.

The effect of the opioid antagonist naloxone on the antipyretic action of acupuncture was studied in rabbits. Naloxone (0.1-0.2 mg/kg) when administered intravenously prior to acupuncture reduced the intensity and duration of the antipyretic action of acupuncture only in the initial stage. The data suggest participation of an endogenous opioid system in initiation of a number of responses mediating the antipyretic effect of acupuncture.