Abstract
Prostaglandin E2 (PGE2) and prostaglandin F(2α) (PGF(2α)) inactivated glycogen synthase and activated glycogen phosphorylase in rat hepatocytes in a dose- and time-dependent manner. These effects were dependent on the presence of Ca2+ in the incubation medium. When glycogen synthase was immunoprecipitated from cells incubated with [32P]P(i) and then treated with PGE2 or PGF(2α), there was increased phosphorylation of the 88 kDa subunit of the enzyme. This phosphorylation affected two CNBr fragments of the glycogen synthase, CB-1 and CB-2, the same fragments that are phosphorylated by different glycogenolytic hormones. No phosphorylation of glycogen synthase by prostaglandins was observed in the absence of Ca2+. Thus the effect of PGE2 and PGF(2α) on these glycogen-metabolizing enzymes supports a role for regulation by prostaglandins of glucose metabolism in parenchymal liver cells.
Original language | English |
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Pages (from-to) | 93-97 |
Journal | Biochemical Journal |
Volume | 261 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Jan 1989 |