title: Low doses of alcohol substantially decrease glucose metabolism in the human brain.
abstract: Moderate doses of alcohol decrease glucose metabolism in the human brain, which has been interpreted to reflect alcohol-induced decreases in brain activity. Here, we measure the effects of two relatively low doses of alcohol (0.25 g/kg and 0.5 g/kg, or 5 to 10 mM in total body H2O) on glucose metabolism in the human brain. Twenty healthy control subjects were tested using positron emission tomography (PET) and FDG after placebo and after acute oral administration of either 0.25 g/kg, or 0.5 g/kg of alcohol, administered over 40 min. Both doses of alcohol significantly decreased whole-brain glucose metabolism (10% and 23% respectively). The responses differed between doses; whereas the 0.25 g/kg dose predominantly reduced metabolism in cortical regions, the 0.5 g/kg dose reduced metabolism in cortical as well as subcortical regions (i.e. cerebellum, mesencephalon, basal ganglia and thalamus). These doses of alcohol did not significantly change the scores in cognitive performance, which contrasts with our previous results showing that a 13% reduction in brain metabolism by lorazepam was associated with significant impairment in performance on the same battery of cognitive tests. This seemingly paradoxical finding raises the possibility that the large brain metabolic decrements during alcohol intoxication could reflect a shift in the substrate for energy utilization, particularly in light of new evidence that blood-borne acetate, which is markedly increased during intoxication, is a substrate for energy production by the brain.
authors.affiliation: National Institute on Drug Abuse, 6001 Executive Blvd., Room 5274, Bethesda, MD 20892, USA. nvolkow@nida.nih.gov
authors.forename: Nora D
authors.initials: ND
authors.lastname: Volkow
authors.forename: Gene-Jack
authors.initials: GJ
authors.lastname: Wang
authors.forename: Dinko
authors.initials: D
authors.lastname: Franceschi
authors.forename: Joanna S
authors.initials: JS
authors.lastname: Fowler
authors.forename: Panayotis Peter K
authors.initials: PP
authors.lastname: Thanos
authors.forename: Laurence
authors.initials: L
authors.lastname: Maynard
authors.forename: S John
authors.initials: SJ
authors.lastname: Gatley
authors.forename: Christopher
authors.initials: C
authors.lastname: Wong
authors.forename: Richard L
authors.initials: RL
authors.lastname: Veech
authors.forename: George
authors.initials: G
authors.lastname: Kunos
authors.forename: Ting
authors.initials: T
authors.lastname: Kai Li
mesh_terms: D000328:Adult; D000777:Anesthetics / Q000494:pharmacology; D001519:Behavior / Q000187:drug effects; D001921:Brain / Q000000981:diagnostic imaging; D001923:Brain Chemistry / Q000187:drug effects*; D002492:Central Nervous System Depressants / Q000097:blood / Q000494:pharmacology*; D003071:Cognition / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism / Q000187:drug effects; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
chemical_list: D000777:Anesthetics; D002492:Central Nervous System Depressants; D006993:Hypnotics and Sedatives; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D000431:Ethanol; D005947:Glucose