title: Acute opioid effects on human brain as revealed by functional magnetic resonance imaging.
abstract: Functional magnetic resonance imaging has been widely used to study brain activation induced either by specific sensory stimulation or motor or cognitive task performance. We demonstrate that functional magnetic resonance imaging can provide information of brain regions involved in opioid-induced central nervous system effects. The reproducibility of the responses in the predefined regions of interest was confirmed by repeated boluses of ultra-short acting mu-opioid receptor agonist remifentanil and saline. We report spatially and temporally detailed information after remifentanil administration. Areas rich in mu-opioid receptors showed strong activations, whereas primary somatosensory cortex that has the lowest density of mu-opioid receptors showed negligible activation. The cingulate, orbitofrontal, posterior parietal and insular cortices, and amygdala showed activation, which was temporally closely related to most subjective sensations that were strongest at 80 to 90 s after drug administration. These areas belong to a circuitry that modulates the affective experience of sensory stimuli.
authors.affiliation: Department of Anesthesia and Intensive Care Medicine, Helsinki University Central Hospital, P.O. Box 340, FIN-00029 HUS, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Leppä
authors.forename: Antti
authors.initials: A
authors.lastname: Korvenoja
authors.forename: Synnöve
authors.initials: S
authors.lastname: Carlson
authors.forename: Paula
authors.initials: P
authors.lastname: Timonen
authors.forename: Sami
authors.initials: S
authors.lastname: Martinkauppi
authors.forename: Jouni
authors.initials: J
authors.lastname: Ahonen
authors.forename: Per H
authors.initials: PH
authors.lastname: Rosenberg
authors.forename: Hannu J
authors.initials: HJ
authors.lastname: Aronen
authors.forename: Eija
authors.initials: E
authors.lastname: Kalso
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects* / Q000502:physiology; D001931:Brain Mapping; D003071:Cognition / Q000187:drug effects*; D005260:Female; D007839:Functional Laterality; D006339:Heart Rate; D006801:Humans; D007262:Infusions, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D010880:Piperidines / Q000008:administration & dosage / Q000494:pharmacology*; D012016:Reference Values; D000077208:Remifentanil; D015203:Reproducibility of Results; D013028:Space Perception
chemical_list: D000701:Analgesics, Opioid; D010880:Piperidines; D000077208:Remifentanil; D010100:Oxygen