Pain: its physiology and rationale for management. Part III. Consequences of current concepts of pain mechanisms related to pain management.

Part III of this review describes the impact that acupuncture, our drug culture, and the gate-control theory have had on our progress in elucidating pain mechanisms and in treating pain syndromes. Whether an analgesis is produced by morphine, acupuncture, or electrical stimulation of an appropriate brain region, the analgesia can be blocked by naloxone, a morphine antagonist. This observation, among others, suggests that similar effector mechanisms involving endogenous opiates serve all three types of analgesia. Although the gate-control theory must continually be revised to accord with new information, it has been a major impetus for stimulating fruitful research.