Metabolism of D-glucosamine and N-acetyl-D-glucosamine in the intact rat.

It has been demonstrated that n-glucosamine and N-acetyln-glucosamine are metabolized in animal tissues to n-fructose via phosphorylated intermediates (14). It has also been shown that n-glucose is converted to n-glucosamine and incorporated into glycoproteins and mucopolysaccharides (Pll), probably through formation of uridine diphosphate derivatives as intermediates (4). Little work has been done, however, to establish the quantitative significance of these pathways in the intact animal. The present work represents a study of the metabolism of n-glucosamine, N-acetyl-n-glucosamine, and n-glucose in normal rats which were deprived of food, and is concerned with the comparative rates of oxidation, conversion to liver glycogen, incorporation as n-glucosamine and sialic acid into macromolecular liver components, and excretion in the urine.