Title: Studies on the enhanced effect of acupuncture analgesia and acupuncture anesthesia by D-phenylalanine (first report)
Abstract:It has been claimed that the mechanism of acupuncture analgesia can be explained in part by endogenous opioids. If so, it might be possible to enhance the analgesic effect of acupuncture by the admini...It has been claimed that the mechanism of acupuncture analgesia can be explained in part by endogenous opioids. If so, it might be possible to enhance the analgesic effect of acupuncture by the administration of endorphins.If D-phenylalanine (DPA), an inhibitor of the endorphin degrading enzyme is administered, the analgesic effect of acupuncture should be prolonged due to the increased level of endorphins.From the changes of the pain threshold (PT), we investigated whether or no t the preadministration of DPA can enhance the analgesic effect of acupuncture in humans. In addition, we examined the inhibitory effect of naloxone.1) In all five subjects whose PT w as raised after acupuncture anesthesia (respondents), the rise in PT were significantly prolonged by DPA.2) Out of 10 subjects whose PT remain ed almost unchanged after acupuncture anesthesia (non-respondents), the PT was increased by DPA in 5 cases.3) The rise in PT was most prominent when DPA w as administered 30 minutes before the start of acupuncture anesthesia.4) In all 4 respond ents in whom the rise in PT persisted after DPA + acupuncture anesthesia, their raised PT dropped after the intravenous injection of naloxone (10 mg).5) These findings show that DPA enhances the analgesic effect of acupuncture by the “endorphin mechanism”.Read More