[The role of the human kidney for glucose homeostasis].

In the postabsorptive state, glucose must be continuously delivered into the circulation in order to meet energy requirements of tissues such as brain cells, which use glucose as their main fuel. Only liver and kidney are able to release glucose into the circulation. Release of glucose into the circulation occurs via two processes: gluconeogenesis, the de novo synthesis of glucose from non-glucose precursors, and glycogenolysis, the breakdown of glycogen. The observations that, in humans renal glucose production contributes approximately 25% to systemic glucose production whereas renal glucose uptake accounts for 20% of systemic glucose removal, indicate an important role of the human kidney for glucose homeostasis.