Activation of protein kinase C mediates insulin regulation of the Na-K pump in cultured skeletal muscle.

Abstract

At first glance, the inclusion of this lecture in this symposium might seem to be a bit superfluous -what possible connection is there between regulation of Na+ -K+ pump activity in skeletal muscle and control of the respiratory and cardiovascular systems? A brief reflection will, of course, provide the answer. Skeletal muscle represents approximately 40% of the body weight and is a major source of K+. Indeed, during muscle exercise muscle activity can lead to a doubling of [K+]o, and a responsive and active Na+ -K+ pump is absolutely essential for continued muscle and cardiovascular function. In addition, the pump plays an important role in control of cardiac and smooth muscle function. Hence, knowledge of the regulatory and signaling mechanisms involved in Na+ -K+ pump activity may also provide information regarding important regulatory mechanisms of respiratory and cardiovascular activity.