The aerobic brain: lactate decrease at the onset of neural activity

• Published in: Neuroscience Vol. 118; no. 1; pp. 7 - 10
• Main Authors: Mangia, S, Garreffa, G, Bianciardi, M, Giove, F, Di Salle, F, Maraviglia, B
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2003; Elsevier
• Subjects: Adult; Biochemistry and metabolism; Biological and medical sciences; Brain - metabolism; Brain Chemistry - physiology; Central nervous system; Down-Regulation - physiology; Energy Metabolism - physiology; Evoked Potentials, Visual - physiology; functional neuronal metabolism; Fundamental and applied biological sciences. Psychology; glia; Humans; Lactic Acid - metabolism; Magnetic Resonance Spectroscopy; Neurons - metabolism; Photic Stimulation; Reaction Time - physiology; single-voxel NMR spectroscopy; Vertebrates: nervous system and sense organs; CMRO 2; CBF; ANLS; glia; CMRglc; PRESS; single-voxel NMR spectroscopy; MRS; fMRI; 1H-MRS; TE; NMR; functional neuronal metabolism; ANOVA; BOLD; LSD; PET; TR; Human; Lactates; single- voxel NMR spectroscopy; Central nervous system; Metabolism; Brain (vertebrata)
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/S0306-4522(02)00792-3

The metabolic events of neuronal energetics during functional activity are still partially unexplained. In particular, lactate (and not glucose) was recently proposed as the main substrate for neurons during activity [Proc Natl Acad Sci USA 91 (1994) 10625]. By means of proton magnetic resonance spectroscopy, lactate was reported to increase during the first minutes of prolonged stimulation [Proc Natl Acad Sci USA 88 (1991) 5829; J Cereb Blood Flow Metab 12 (1992) 584; Magn Reson Med 35 (1996) 143], but the studies reported thus far suffered from low temporal resolution. In the present study we used a time-resolved proton magnetic resonance spectroscopy strategy in order to analyse the evolution of lactate during the early seconds following a brief visual stimulation (event-related design). A significant decrease in lactate concentration was observed 5 s after the stimulation, while a recovering of the baseline was observed at 12 s.