Temporal dynamics of lactate concentration in the human brain during acute inspiratory hypoxia
Article first published online: 29 NOV 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging
Volume 37, Issue 3, pages 739–745, March 2013
How to Cite
Harris, A. D., Roberton, V. H., Huckle, D. L., Saxena, N., Evans, C. J., Murphy, K., Hall, J. E., Bailey, D. M., Mitsis, G., Edden, R. A.E. and Wise, R. G. (2013), Temporal dynamics of lactate concentration in the human brain during acute inspiratory hypoxia. J. Magn. Reson. Imaging, 37: 739–745. doi: 10.1002/jmri.23815
- Issue published online: 15 FEB 2013
- Article first published online: 29 NOV 2012
- Manuscript Accepted: 9 AUG 2012
- Manuscript Received: 9 FEB 2012
- National Institutes of Health (NIH). Grant Number: P41 EB015909
- Wellcome Trust
- Higher Education Funding Council for Wales and the UK Medical Research Council
- cerebral lactate;
- magnetic resonance spectroscopy;
- impulse response function
To demonstrate the feasibility of measuring the temporal dynamics of cerebral lactate concentration and examine these dynamics in human subjects using magnetic resonance spectroscopy (MRS) during hypoxia.
Materials and Methods:
A respiratory protocol consisting of 10-minute baseline normoxia, 20-minute inspiratory hypoxia, and ending with 10-minute normoxic recovery was used, throughout which lactate-edited MRS was performed. This was repeated four times in three subjects. A separate session was performed to measure blood lactate. Impulse response functions using end-tidal oxygen and blood lactate as system inputs and cerebral lactate as the system output were examined to describe the dynamics of the cerebral lactate response to a hypoxic challenge.
The average lactate increase was 20% ± 15% during the last half of the hypoxic challenge. Significant changes in cerebral lactate concentration were observed after 400 seconds. The average relative increase in blood lactate was 188% ± 95%. The temporal dynamics of cerebral lactate concentration was reproducibly demonstrated with 200-second time bins of MRS data (coefficient of variation 0.063 ± 0.035 between time bins in normoxia). The across-subject coefficient of variation was 0.333.
The methods for measuring the dynamics of the cerebral lactate response developed here would be useful to further investigate the brain's response to hypoxia. J. Magn. Reson. Imaging 2013;37:739–745. © 2012 Wiley Periodicals, Inc.