Mindfulness-Meditation-Based Pain Relief Is Not Mediated by Endogenous Opioids. Author: Zeidan F1, Adler-Neal AL2, Wells RE3, Stagnaro E4, May LM5, Eisenach JC6, McHaffie JG2, Coghill RC7. Affiliation: 1Department of Neurobiology and Anatomy, fzeidan@wakehealth.edu. 2Department of Neurobiology and Anatomy. 3Department of Neurology, and. 4Department of Psychology, Wake Forest University, Winston-Salem, North Carolina 27109. 5Department of Biology, University of Oregon, Eugene, Oregon 97403, and. 6Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157. 7Department of Anesthesiology, Cin Conference/Journal: J Neurosci. Date published: 2016 Mar 16 Other: Volume ID: 36 , Issue ID: 11 , Pages: 3391-7 , Special Notes: doi: 10.1523/JNEUROSCI.4328-15.2016. , Word Count: 307 Mindfulness meditation, a cognitive practice premised on sustaining nonjudgmental awareness of arising sensory events, reliably attenuates pain. Mindfulness meditation activates multiple brain regions that contain a high expression of opioid receptors. However, it is unknown whether mindfulness-meditation-based analgesia is mediated by endogenous opioids. The present double-blind, randomized study examined behavioral pain responses in healthy human volunteers during mindfulness meditation and a nonmanipulation control condition in response to noxious heat and intravenous administration of the opioid antagonist naloxone (0.15 mg/kg bolus + 0.1 mg/kg/h infusion) or saline placebo. Meditation during saline infusion significantly reduced pain intensity and unpleasantness ratings when compared to the control + saline group. However, naloxone infusion failed to reverse meditation-induced analgesia. There were no significant differences in pain intensity or pain unpleasantness reductions between the meditation + naloxone and the meditation + saline groups. Furthermore, mindfulness meditation during naloxone produced significantly greater reductions in pain intensity and unpleasantness than the control groups. These findings demonstrate that mindfulness meditation does not rely on endogenous opioidergic mechanisms to reduce pain. SIGNIFICANCE STATEMENT: Endogenous opioids have been repeatedly shown to be involved in the cognitive inhibition of pain. Mindfulness meditation, a practice premised on directing nonjudgmental attention to arising sensory events, reduces pain by engaging mechanisms supporting the cognitive control of pain. However, it remains unknown if mindfulness-meditation-based analgesia is mediated by opioids, an important consideration for using meditation to treat chronic pain. To address this question, the present study examined pain reports during meditation in response to noxious heat and administration of the opioid antagonist naloxone and placebo saline. The results demonstrate that meditation-based pain relief does not require endogenous opioids. Therefore, the treatment of chronic pain may be more effective with meditation due to a lack of cross-tolerance with opiate-based medications. Copyright © 2016 the authors 0270-6474/16/363391-07$15.00/0. KEYWORDS: cognitive; mindfulness meditation; naloxone; opioid; pain PMID: 26985045 [PubMed - in process]