The use of glucose-C14 for the evaluation of the pathways of glucose metabolism.

http://www.jbc.org/content/234/9/2246.full.pdf

Glycolytic pathways and lipogenesis in mammary glands of lactating and nonlactating normal rats.

In mammals and most other organisms, the first step in the metabolism of glucose is its phosphorylation to glucose-6-phosphate. The metabolic pathways of glucose-6-phosphate utilization can be conveniently divided into two major groups: a) pathways in which glucose is broken down to triose phosphate and will be designated as triose pathways ; and b) pathways that do not yield triose-phosphate and which will be designated here as non-triose pathways. Until fairly recently, it was generally held that glucose is catabolized to triose phosphate solely by the reactions of the classical Embden-Meyerhof (E. M.3) pathway. An alternate pathway of glucose phosphate catabolism in mammalian tissues has been known since about 1930 from Warburg’s discovery of the direct oxidation of glucose-6-phosphate. By 1936, it was known that the aldehyde carbon of glucose-6-phos-phate is decarboxylated to CO2 and a pentose phosphate is formed; and Dickens and Lipmann proposed schemes for glucose oxidation based on these observations. However, little attention was paid to these schemes and the mechanism of this pathway remained obscure until about 1950. Since that time, the detailed operation of this scheme has been elucidated by the work of several laboratories, especially those of Horecker and Racker. The pentose pathway yields CO2 and 1 mole of triose phosphate per mole of glucose, whereas the E. M. pathway yields two moles of triose phosphate, and the subsequent metabolism of the triose phosphate is common to both pathways.

The use of glucose-14C in the study of the pathways of glucose metabolism in mammalian tissues

Lactose Synthesis: IV. THE SYNTHESIS OF MILK CONSTITUENTS AFTER UNILATERAL INJECTION OF GLYCEROL-1,3-C14 INTO THE PUDIC ARTERY

/pdf/thiamin-and-niacin-in-ruminant-nutrition-51p29rsuam.pdf

Georg B. Brubacher

Papers

The pentose cycle as a pathway for glucose metabolism in intact lactating dairy cows.