The relationship between uracil nucleotide concentrations and glycogen synthesis in hepatocytes from fed and fasted rats.

The relationship between glycogen synthesis and uracil nucleotide content was studied in rat hepatocytes. When hepatocytes were incubated in the presence of uridine in the incubation medium there was an increase in the rate of incorporation of U-14C-glucose into glycogen. In hepatocytes incubated in the absence of uridine for 1 hr there were large decreases in the cellular contents of UDPG and UTP, while in the presence of 5 mM uridine the concentrations of these nucleotides increased 2 to 3 fold. In hepatocytes from fasted rats uracil nucleotide contents were lower than in hepatocytes from fed rats and the effect of uridine on glycogen synthesis was greater.