Normal Muscle Energy Metabolism

Abstract

In all cells, ATP plays a central role in providing a chemical form of potential energy which is enzymatically converted through specific coupling mechanisms into useful work of the cell, e.g. macromolecular synthesis, osmotic, electrical and mechanical work. Striated muscle cells, and skeletal muscle cells in particular, are excellent preparations for studies of the regulation of this energy production and utilization. The reason is that, in contrast with other cells which operate under steady physiological states, the metabolic rate of muscle cells can be increased ten- to fifty-fold above the basal rate by stimulating the muscle to mechanical activity. This large increase in metabolic rate allows exploration of non-steady state energy perturbations, which gives important insight into general aspects of metabolic regulation.