Carbohydrate Metabolism of the Liver in Normal Man under Varying Dietary Conditions

Abstract

The glucose and urea production and the uptake of gluconeogenic precursors by the liver were measured with the liver vein catheterization technique in two series of healthy subjects after 4 days on a well-defined normo-caloric diet. After a normal mixed diet the net splanchnic glucose production was 0.87 mmol/min. The glucose derived from maximum gluconeogenesis was 0.31 mmol/min. By using a liver biopsy technique in a similar series, the glycogenolysis was found to be 0.54 mmol glucose/min. After a carbohydrate-poor diet the splanchnic glucose production had decreased to 0.30 mmol/min. In this situation the liver was deprived of most of its glycogen, as shown earlier by direct determination of glycogen in liver biopsy specimens. The uptake of gluconeogenic substrates corresponded to the net glucose production. The decreased glucose production during carbohydrate-poor diet did not result in any significant change of the blood glucose level. This indicates a considerable decrease of the peripheral uptake of glucose.

Key Words:

• Carbohydrate metabolism
• diet
• gluconeogenesis
• glycogenolysis
• ketone bodies
• liver glucose production
• liver glycogen
• liver vein catheterization
• quantitative
• starvation