Factors affecting the incorporation of radioactive phosphate into the pentosenucleic acids of brain slices

Abstract

The incorporation of radioactive phosphate into the pentosenucleic acid of cat-brain slices respiring in a Krebs-Ringer bicarbonate medium was increased by the addition of glucose or mannose, but not by fructose or galactose. The incorporation of P32 was decreased greatly by rendering the conditions anaerobic, or by dispersing the tissue. Pyruvate or lactate supported the incorporation of P32 into the pentosenucleic acid, but not succinate, L(+)-glutamate, D(-)-glutamate, alpha-ketoglutarate, citrate or L-malate. A wide range of metabolic inhibitors that depress the O2 consumption of brain slices inhibited the incorporation of P32. 2,4-Dinitrophenol in a concn. that does not decrease the O2 consumption of brain slices decreased the incorporation of P32. The similarity between the conditions that adversely affect the incorporation of P32 into the pentosenucleic acid of brain slices and those that cause a failure of brain slices to maintain their concn. of phosphocreatine is commented upon.