The Croonian Lecture, 1963 Gluconeogenesis

Abstract

I am using the term gluconeogenesis in this lecture to denote any new formation of carbohydrate from non-carbohydrates. These non-carbohydrates include amino acids, as well as the lactate continuously produced in the body, e.g. in blood cells and in the exercised muscles. When lactate is the precursor of carbohydrate the formation of glucose from it constitutes a re-formation rather than a new formation as the lactate has been derived from glucose. But as the enzymic mechanisms of glucose formation from lactate and from amino acids are essentially the same, it is reasonable to treat them jointly. Gluconeogenesis is a biosynthetic process of major importance. I intend to review first some aspects of the physiological role of gluconeogenesis. This will lead to the fact that the amounts of carbohydrate which are synthesized vary within very wide limits—between almost nil and perhaps 200 g per day in the case of the human adult—and this will bring me to the main subject: the question of how the rate of gluconeogenesis is regulated and adjusted to changing needs.