Cellular oxygen consumption depends on body mass.
Porter, Richard K., and Martin D. Brand.
Department of Biochemistry, University of Cambridge, Tennis Court
Road, Cambridge CB2 1QW. UK.
APStracts 2:0107R, 1995.
Hepatocytes were isolated from nine species of mammal of different
body mass (and standard metabolic rate). The cells were incubated
under identical conditions and oxygen consumption measured. The rate
of oxygen consumption (per unit mass of cells) scaled with body mass
with exponent -0.18. In general, there was a 5.5-fold decrease in
oxygen consumption rate with a 12500-fold increase in body mass. The
decrease in oxygen consumption rate was not due to an increase in
cell volume with increasing body mass but to a decrease in intrinsic
metabolic activity of the cells. This novel finding confirms and
explains the decrease in oxygen consumption rate measured in tissue
slices from larger mammals by Krebs (9) and recently by Couture and
Hulbert (4).
Received 26 October 1994; accepted in final form 20 April 1995.
APS Manuscript Number R621-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 25 April 1995.