Intrinsic Mechanisms of Pain Inhibition: Activation by Stress

• Published in: Science (American Association for the Advancement of Science) Vol. 226; no. 4680; pp. 1270 - 1277
• Main Authors: Terman, Gregory W., Shavit, Yehuda, Lewis, James W., Cannon, J. Timothy, Liebeskind, John C.
• Format: Journal Article
• Language: English
• Published: Washington, DC The American Association for the Advancement of Science 14-12-1984; American Association for the Advancement of Science
• Subjects: Adaptation, Physiological; Adrenalectomy; Analgesia; Anesthesia; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Behavioral neuroscience; Biological and medical sciences; Brain research; Brain stem; Brain Stem - physiology; Conditioning (Psychology); Electroshock; Endorphins - physiology; Histamine - physiology; Humans; Hypophysectomy; Immunosuppression; Lesions; Local anesthesia. Pain (treatment); Medical sciences; Morphine; Naltrexone - pharmacology; Neoplasms - physiopathology; Nociceptors - physiology; Observations; Opiates; Opioid analgesics; Pain; Pain - physiopathology; Pentobarbital - pharmacology; Physiological aspects; Prevention; Rats; Stress (Physiology); Stress, Physiological - physiopathology; Tumors; Stress; Pain
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.6505691

Portions of the brain stem seem normally to inhibit pain. In man and laboratory animals these brain areas and pathways from them to spinal sensory circuits can be activated by focal stimulation. Endogenous opioids appear to be implicated although separate nonopioid mechanisms are also evident. Stress seems to be a natural stimulus triggering pain suppression. Properties of electric footshock have been shown to determine the opioid or nonopioid basis of stress-induced analgesia. Two different opioid systems can be activated by different footshock paradigms. This dissection of stress analgesia has begun to integrate divergent findings concerning pain inhibition and also to account for some of the variance that has obscured the reliable measurement of the effects of stress on tumor growth and immune function.