Insulin antagonises the growth hormone-mediated increase in the activity of phosphatidate phosphohydrolase in isolated rat hepatocytes.
Rat hepatocytes were incubated in monolayer culture, under serum-free conditions for 8 h. Rat growth hormone (up to 100 nM) increased the activity of phosphatidate phosphohydrolase by up to 47%. Insulin (500 pM or 35 nM), cycloheximide or actinomycin D reversed this effect. The ability of growth hormone to modify the effects of insulin is discussed in relation to the control of the phosphohydrolase activity and glycerolipid synthesis.
D000818:Animals; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D013006:Growth Hormone / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology*; D008099:Liver / Q000201:enzymology*; D010711:Phosphatidate Phosphatase / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D014176:Protein Biosynthesis; D051381:Rats
D007328:Insulin; D003609:Dactinomycin; D003907:Dexamethasone; D013006:Growth Hormone; D003513:Cycloheximide; D010744:Phosphoric Monoester Hydrolases; D010711:Phosphatidate Phosphatase