Stimulation by insulin and prostaglandin E1 of glucose metabolism and inhibition of lipolytic action of theophylline on fat cells in the absence of K+.

Abstract

Insulin and prostaglandin E1 inhibited the lipolytic action of theophylline on white fat cells and stimulated the metabolism of glucose by cells isolated and incubated in K+- free buffer. Fat cells incubated in K+-free buffer metabolized more glucose than in regular buffer and under certain conditions a marked increase in glucose metabolism due to insulin was bestseen in the presence of theophylline. The addition of tetraphenylborate, a K+ complexing agent, did not block the action of insulin in K+- free buffer. These results indicate that the mechanisms by which insulin and prostaglandin E1 affect fat cell metabolism are not dependent upon extracellular K+. (Endocrinology 83: 548, 1968)