The Stimulation of Glycogen Synthesis and of Glycogen Synthetase in the Liver by the Administration of Glucose

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  • Note added in proof (June 14, 1967). J. S. Bishop and J. Larner [J. Biol. Chem. 242 (1967) 1354] have recently reported that, after treatment of dogs with glucose and insulin, the activity of liver phosphorylase measured in the absence of added AMP is greatly diminished. We have not observed this effect in mice treated as in experiment No. 2 of Table 3; therefore, the increased incorporation of glucose into glycogen observed in this experiment cannot be attributed to an inhibition of phosphorylase.

Abstract

The intravenous administration of glucose to the mouse stimulates 15–20 and up to 40-fold the conversion of glucose to glycogen in the liver. This effect is observed in the normally fed as well as in the fasted animal and requires 5 min to reach its full development. At that time, the hepatic concentration of glucose 6-phosphate and of UDPG is markedly lowered whereas the activity of glycogen synthetase, when measured in a concentrated liver homogenate, is greatly increased. The rate of glycogen synthesis is not correlated with the concentration of glucose in the liver but is highly significantly correlated with the activity of liver glycogen synthetase.

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