AJP - Regulatory, Integrative and Comparative Physiology, Vol 236, Issue 1 31-R39, Copyright © 1979 by American Physiological Society
Metabolism of the acutely ischemic dog heart. II. Interpretation of a model
D. Garfinkel and M. J. Achs
The glycolytic oscillations occurring in an acutely ischemic dog heart are
analyzed with a computer model. The major regulations of the glycolytic
pathway flux occur at phosphohexose isomerase, which is inhibited by
accumulated pentose shunt intermediates; at phosphorylase, which shapes the
first cycle of the oscillation; and at aldolase, which shapes the last two
cycles. Aldolase is not under normal substrate control. Its activity, and
that of some subsequent glycolytic enzymes, appears to be regulated by
known interactions with the muscle proteins. The mitochondria become
reduced as a result of anoxia, and their metabolism reorganizes to export
rather than import reducing equivalents. It is in general feasible to
account for the behavior of this preparation in terms of the known
metabolism of less severely perturbed hearts, especially (but not
completely) in terms of effects of anoxia. The reasons for the
inapplicability of the crossover theorem previously used to analyze this
preparation are described.
