CLAUDE BERNARD'S experiments of a century ago stimulated interest in the relation between functions of the brain and glucose metabolism. Some authors, including Jelliffe,1have since reported metabolic abnormalities in multiple sclerosis; the reported changes consisted in a low fasting serum inorganic phosphorus3and a high fasting serum cholesterol.2More recent studies in patients with multiple sclerosis revealed elevation of the fasting blood pyruvic acid concentrations and an excessive accumulation of this substance following the ingestion of glucose; decreased glucose tolerance and abnormally great and prolonged fall in serum inorganic phosphate were also observed.4These workers confirmed earlier reports of a low fasting serum inorganic phosphorus and a high fasting serum cholesterol. The experiments reported here were designed to elucidate further the nature of metabolic defect already reported to occur in multiple sclerosis. Our studies did not confirm the finding of elevated fasting pyruvic acid concentrations