The short-term effect of pituitary growth hormone on the catabolism of fat in the liver

Abstract

The in vitro oxidation of octanoate was studied in the livers of normal and diabetic rats injected 6 and 12 hours previously with growth hormone. In normal rats there is an inhibition of fatty acid oxidation to CO2 and water 6 hours after the injection of the hormone, but in diabetic animals this inhibition is not obtained. In normal rats there is a stimulation of fatty acid oxidation, both as far as the 2-C fragment and to CO2 and water, 12 hours after the injection of the hormone. In diabetic rats there is also a stimulation of the rate of 2-C-fragment formation at this time interval, but no increase in the rate of oxidation of the 2-C units. It is suggested that the inhibition of fatty acid oxidation found 6 hours after the injection is due to a release of insulin caused by the pancreatropic effect of the growth hormone, and not by the growth hormone itself. The effect of growth hormone is to produce an increased rate of fat degradation.