The utilization of glucose by tissue slices of liver and other organs of the domestic fowl

The utilizations of glucose-1-14C, glucose-6-14C, and glucose-U-14C by liver slices from the immature and the laying domestic fowl have been evaluated. The relative degrees of incorporation of C-1 and C-6 into CO2, total lipid, fatty acids, and glyceride-glycerol resulted in C-1/C-6 quotients that approximated unity for both groups of fowl. The amounts of incorporation of the two specifically labelled carbon atoms into glycogen were significantly different for liver from the immature bird, but not for that from the laying fowl. These results indicate that the commencement of egg production is not accompanied by activation of the phosphogluconate oxidative pathway.When compared on a DNA basis, the amounts of isotope from glucose-U-14C incorporated into CO2, total lipid, fatty acids, glyceride-glycerol, and glycogen by liver slices from the immature fowl were almost equal to the degrees of incorporation observed following incubation of liver obtained from laying birds. The results with glucose-U-14C suggest that little or no modification of carbohydrate metabolism occurred when sexual maturity was reached.Yields of 14CO2 from the oxidation of glucose-1-14C and glucose-6-14C by various fowl tissues other than the liver are also reported. The observed C-1/C-6 ratios were in general lower than values reported in the literature for corresponding mammalian tissues, except that the quotients for fowl heart and ovary were higher than those reported for rat heart and ovary.