Interleukin 1 beta regulates glycogen metabolism in primary cultured rat hepatocytes

We examined the effects of human recombinant IL-1 beta on glycogen metabolism in cultured rat hepatocytes. When IL-1 beta was present at 8 nM in the culture medium for 15 hours prior to cell harvest, glycogen storage in hepatocytes was lowered approximately by 60% of the control. The enzymatic activity of glycogen synthase I in the IL-1 beta-treated cells (8 nM) was decreased by 70%; however, the activity ratio of the synthases I to D was not different from the untreated. In addition, the activity of glycogen phosphorylase a, the active form of phosphorylase involved in glycogenolysis, was increased by approximately 27% while the total phosphorylase activity was not changed. The data demonstrate for the first time that IL-1 beta lowers the intracellular glycogen contents in primary cultured rat hepatocytes.