Studies on the Perfused Rat Liver: I. Effects of Glucagon and Insulin on Glucose Metabolism

A method is described for perfusing the isolated rat liver with a solution of known composition without red blood cells, which also permits convenient monitoring of viability and function by measuring flow rate. The effects of insulin and glucagon were studied on urea synthesis, on glucose production and utilization, and on incorporation of glucose-U-C-14 label into Co₂, protein, glycogen, total lipids, and fatty acids. Under the experimental conditions employed, the liver is capable of gluconeogenesis; however, it takes up and metabolizes about twice as much glucose as it releases. Glucagon increased glucose and urea production but markedly reduced incorporation of glucose-U-C-14 into Co₂ and protein. The only statistically significant effect of insulin was to increase incorporation of label into fatty acids.