Measurement of changes in opioid receptor binding in vivo during trigeminal neuralgic pain using [11C] diprenorphine and positron emission tomography.
The binding of [11C]diprenorphine to mu, kappa, and delta subsites in cortical and subcortical structures was measured by positron emission tomography in vivo in six patients before and after surgical relief of trigeminal neuralgia pain. The volume of distribution of [11C]diprenorphine binding was significantly increased after thermocoagulation of the relevant trigeminal division in the following areas: prefrontal, insular, perigenual, mid-cingulate and inferior parietal cortices, basal ganglia, and thalamus bilaterally. In addition to the pain relief associated with the surgical procedure, there also was an improvement in anxiety and depression scores. In the context of other studies, these changes in binding most likely resulted from the change in the pain state. The results suggest an increased occupancy by endogenous opioid peptides during trigeminal pain but cannot exclude coexistent down-regulation of binding sites.
Human Physiology and Pain Research Laboratory, University of Manchester Rheumatic Diseases Centre, Hope Hospital, Salford, United Kingdom.
A K
AK
Jones
N D
ND
Kitchen
H
H
Watabe
V J
VJ
Cunningham
T
T
Jones
S K
SK
Luthra
D G
DG
Thomas
D000368:Aged; D002250:Carbon Radioisotopes; D004174:Diprenorphine / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009292:Narcotic Antagonists / Q000378:metabolism; D011869:Radioligand Assay; D011957:Receptors, Opioid / Q000502:physiology*; D014055:Tomography, Emission-Computed; D014277:Trigeminal Neuralgia / Q000378:metabolism / Q000503:physiopathology*
D002250:Carbon Radioisotopes; D009292:Narcotic Antagonists; D011957:Receptors, Opioid; D004174:Diprenorphine