Acute hypoxia increases the cerebral metabolic rate: a magnetic resonance imaging study

Mark Bitsch Vestergaard, Ulrich Lindberg, Niels Jacob Aachmann-Andersen, Kristian Lisbjerg, Søren Thinus Just Christensen, Ian Law, Peter Rasmussen, Niels V Olsen, Henrik Bw Larsson

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

55 Citationer (Scopus)
459 Downloads (Pure)

Abstract

The aim of the present study was to examine changes in cerebral metabolism by magnetic resonance imaging of healthy subjects during inhalation of 10% O2 hypoxic air. Hypoxic exposure elevates cerebral perfusion, but its effect on energy metabolism has been less investigated. Magnetic resonance imaging techniques were used to measure global cerebral blood flow and the venous oxygen saturation in the sagittal sinus. Global cerebral metabolic rate of oxygen was quantified from cerebral blood flow and arteriovenous oxygen saturation difference. Concentrations of lactate, glutamate, N-acetylaspartate, creatine and phosphocreatine were measured in the visual cortex by magnetic resonance spectroscopy. Twenty-three young healthy males were scanned for 60 min during normoxia, followed by 40 min of breathing hypoxic air. Inhalation of hypoxic air resulted in an increase in cerebral blood flow of 15.5% (p = 0.058), and an increase in cerebral metabolic rate of oxygen of 8.5% (p = 0.035). Cerebral lactate concentration increased by 180.3% ([Formula: see text]), glutamate increased by 4.7% ([Formula: see text]) and creatine and phosphocreatine decreased by 15.2% (p[Formula: see text]). The N-acetylaspartate concentration was unchanged (p = 0.36). In conclusion, acute hypoxia in healthy subjects increased perfusion and metabolic rate, which could represent an increase in neuronal activity. We conclude that marked changes in brain homeostasis occur in the healthy human brain during exposure to acute hypoxia.
OriginalsprogEngelsk
TidsskriftJournal of Cerebral Blood Flow and Metabolism
Vol/bind36
Udgave nummer6
Sider (fra-til)1046-1058
Antal sider13
ISSN0271-678X
DOI
StatusUdgivet - jun. 2016

Citationsformater