Short Term Regulation of Mouse Pyruvate Dehydrogenase Complex by Insulin

Pyruvate dehydrogenase complex activity and its regulating factors were measured in diabetic mice in a starved or unstarved state. Both in starved and unstarved groups of normal mice, pyruvate dehydrogenase complex activity increased equally by insulin administration. On the other hand, in an unstarved group of diabetic mice, no change in pyruvate dehydrogenase complex activity was observed with the same treatment. With the starved group it increased within 10 minutes and recovered to the base value level in 30 minutes. As a result of studies on active form of pyruvate dehydrogenase complex in the liver and its regulating factors, it was found that no corresponding relation existed between the enzyme complex activity and its regulating factors. We found that unlike the normal mice, not only the previously known regulating mechanism but also other factors affected the pyruvate dehydrogenase complex activity in the diabetic mice.