Hepatic acetoacetyl-CoA deacylase activity in rats fed ethyl chlorophenoxyisobutyrate (CPIB).

Intact or sonicated mitochondria from the livers of rats fed a diet containing 0.2% ethyl chlorophenoxyisobutyrate (CPIB) for 3 wk showed acetoacetyl-CoA deacylase activity enhanced 26 and 39%, respectively, over that shown by comparable fractions from rats fed the same diet without CPIB. The corresponding supernatant fractions did not differ in activity. The enhanced activity of mitochondrial acetoacetyl-CoA deacylase in the livers of the CPIB-treated rats could effectively decrease the amount of acetoacetyl CoA available within the cell for synthetic processes.