Brain glucose metabolism in hypobaric hypoxia.
Harik, Sami I., W. David Lust, Stephen C. Jones, Karen L. Lauro,
Svetlana Pundik, and Joseph C. Lamanna.
Departments of Neurology and Neurological Surgery, Case Western
Reserve University School of Medicine, and the Department of
Neurosciences, Cleveland Clinic Foundation.
APStracts 2:0125A, 1995.
Hypobaric hypoxia at half atmosphere of pressure for 3 weeks was
reported to increase the brain capillary density, and glucose
transport at the blood-brain barrier in the adult rat. We examined
the metabolic concomitants of these alterations in rats subjected to
the same hypoxic insult. Hypoxic rats increased their brain glucose
and lactate concentrations and decreased their brain glycogen.
However, hypoxia had no significant effects on regional brain levels
of ATP and phosphocreatine, or on intracellular pH, indicating
successful adaptation to the hypoxic insult. 2-Deoxyglucose studies
showed that hypoxia increased the regional metabolic rate for glucose
by 10 to 40%. These results indicate increased glycolysis in the
hypoxic rat brain, which probably underlies the increased density of
glucose transporters in brain microvessels and the increased blood
-to-brain glucose influx in hypoxia.
Received 4 November 1994; accepted in final form 27 February
1995.
APS Manuscript Number A1135-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 4 April 1995.