Effect of morphine and naloxone on acupuncture analgesia in unrestrained rats

Experiments on unrestrained rats showed that electroacupuncture of an acupuncture point distinctly reduces the nociceptive response to electrical stimulation of the base of the tail. Morphine, in a subanalgesic dose (5 mg/kg), potentiated the analgesic effect of acupuncture. Naloxone, in a dose of 5 mg/kg, completely abolished acupuncture analgesia. The possible mechanisms of analgesia production by electroacupuncture are discussed.Department of Pharmacology, I. P. Pavlov First Leningrad Medical Institute. Course of Reflex Therapy, S. M. Kirov Leningrad Postgraduate Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 11, pp. 566–569, November, 1979.