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Intracranial Pharmacotherapy and Pain Assays in Rodents
Published on: April 9, 2019
Endogenous opioids mediate left dorsolateral prefrontal cortex rTMS-induced analgesia
Joseph J Taylor1, Jeffrey J Borckardt, Mark S George
1Brain Stimulation Laboratory, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, USA Ralph H. Johnson VA Medical Center, Charleston, SC, USA.
Pain
|March 27, 2012
Summary
Repetitive transcranial magnetic stimulation (rTMS) reduces pain by activating the brain's natural opioid system. Blocking these opioids with naloxone significantly reduced rTMS's pain-relieving effects.
Area of Science:
- Neuroscience
- Pain Management
- Pharmacology
Background:
- Undertreated pain and opioid abuse present significant challenges.
- Repetitive transcranial magnetic stimulation (rTMS) shows analgesic effects, but its mechanisms are unclear.
- Dorsolateral prefrontal cortex (DLPFC) rTMS may modulate pain via the opioidergic system.
Purpose of the Study:
- To investigate if left DLPFC rTMS-induced analgesia is dependent on μ-opioid activity.
- To determine the role of endogenous opioids in rTMS pain relief.
Main Methods:
- Sham-controlled, double-blind, crossover study with 24 healthy volunteers.
- rTMS applied to left DLPFC after saline or naloxone pretreatment.
- Quantitative sensory testing assessed pain and allodynia.
Main Results:
- Real rTMS significantly reduced hot pain and allodynia compared to sham.
- Naloxone pretreatment diminished the analgesic effects of real rTMS.
- Left DLPFC rTMS-induced analgesia requires opioid activity.
Conclusions:
- rTMS activates endogenous opioidergic pain relief pathways in the brain.
- rTMS may be a non-invasive strategy to enhance opioid-mediated pain management.
- Further research is needed on chronic dosing and augmenting opioid actions.
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