Pain activation of human supraspinal opioid pathways as demonstrated by [11C]-carfentanil and positron emission tomography (PET)
- PMID: 12406535
- DOI: 10.1016/S0304-3959(02)00266-X
Pain activation of human supraspinal opioid pathways as demonstrated by [11C]-carfentanil and positron emission tomography (PET)
Abstract
The role of the supraspinal endogenous opioid system in pain processing has been investigated in this study using positron emission tomography imaging of [11C]-carfentanil, a synthetic, highly specific mu opioid receptor (mu-OR) agonist. Eight healthy volunteers were studied during a baseline imaging session and during a session in which subjects experienced pain induced by applying capsaicin topically to the dorsal aspect of the left hand. A pain-related decrease in brain mu-OR binding was observed in the contralateral thalamus consistent with competitive binding between [11C]-carfentanil and acutely released endogenous opioid peptides. This decrease varied directly with ratings of pain intensity. These results suggest that the supraspinal mu-opioid system is activated by acute pain and thus may play a substantial role in pain processing and modulation in pain syndromes.
References
-
- Amanzio M, Benedetti F. Neuropharmacological dissection of placebo analgesia: expectation-activated opioid systems versus conditioning-activated specific subsystems. J Neurosci. 1999;19:484-494.
-
- Anderson WS, Sheth RN, Bencherif B, Campbell JN, Frost JJ. Naloxone increases pain induced by topical capsaicin in healthy volunteers. Pain. 2002;99:207-216.
-
- Ashburner J, Friston KJ. Non-linear spatial normalization using basis functions. Hum Brain Mapp. 1999;7:254-266.
-
- Bartenstein PA, Duncan JS, Prevett MC. Investigation of the opioid system in absence seizures with positron emission tomography. J Neurol Neurosurg Psychiatry. 1993;56:1295-1302.
-
- Barton C, Basbaum AI, Fields HL. Dissociation of supraspinal and spinal actions of morphine: a quantitative evaluation. Brain Res. 1980;188:487-498.
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