Evidence for modulation of opioidergic activity in central vestibular processing: A [(18)F] diprenorphine PET study.
Animal and functional imaging studies had identified cortical structures such as the parieto-insular vestibular cortex, the retro-insular cortex, or the anterior cingulate cortex belonging to a vestibular cortical network. Basic animal studies revealed that endorphins might be important transmitters involved in cerebral vestibular processing. The aim of the present study was therefore to analyse whether the opioid system is involved in vestibular neurotransmission of humans or not. Changes in opioid receptor availability during caloric air stimulation of the right ear were studied with [(18)F] Fluoroethyl-diprenorphine ([(18)F]FEDPN) PET scans in 10 right-handed healthy volunteers and compared to a control condition. Decrease in receptor availability to [(18)F]FEDPN during vestibular stimulation in comparison to the control condition was significant at the right posterior insular cortex and the postcentral region indicating more endogenous opioidergic binding in these regions during stimulation. These data give evidence that the opioidergic system plays a role in the right hemispheric dominance of the vestibular cortical system in right-handers.
Department of Neurology, University of Mainz, Langenbeckstr. 1, 55131 Mainz, Germany. baierb@uni-mainz.de
Bernhard
B
Baier
Sandra
S
Bense
Frank
F
Birklein
Hans-Georg
HG
Buchholz
Anja
A
Mischke
Matthias
M
Schreckenberger
Marianne
M
Dieterich
D000328:Adult; D001794:Blood Pressure; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D004174:Diprenorphine / Q000031:analogs & derivatives / Q000378:metabolism; D004244:Dizziness / Q000000981:diagnostic imaging / Q000378:metabolism*; D006801:Humans; D008297:Male; D010812:Physical Stimulation; D049268:Positron-Emission Tomography; D011957:Receptors, Opioid / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology; D014717:Vertigo / Q000000981:diagnostic imaging / Q000378:metabolism*; D014722:Vestibule, Labyrinth / Q000502:physiology*
C411951:6-O-(2-(18F)fluoroethyl)-6-O-desmethyldiprenorphine; D011957:Receptors, Opioid; D004174:Diprenorphine