Oxidation of Fructose by Brain in Vitro

Fructose does not maintain the electrical activity of the cerebral cortex in the hepatectomized animal (1). However, whole brain (2) and cortex (3) oxidize fructose in vitro. These facts may be explained by assuming that the brain cells are impermeable to fructose in viva, or that the oxidation of fructose is not concerned in the maintenance of cortical activity. The latter supposition makes it necessary to assume that the metabolism of fructose by brain differs from the metabolism of glucose, since glucose does support cortical activity in the hepatectomized animal (1). In the present work the oxidation of fructose by brain preparations was studied in vitro. The data obtained indicate that the oxidation of fructose by brain in vitro follows the same pattern as the oxidation of glucose. Thus, the data support the hypothesis that brain cells are impermeable to fructose in vivo. Materials and Methods