The metabolism and binding of catecholamines by the hepatic microsomal fraction of the rat

Acetone enhanced the metabolism of adrenaline and noradrenaline, suggesting that both are type II substrates. Catecholamines possess all the characteristics of type II compounds and are metabolized by the hepatic microsomal mixed function oxidase. The products of metabolism however, remain to be identified. The physiological significance of the process, if any, is not known. Catecholamines at even higher concentrations, up to 1mM, have no direct competitive effect on the metabolism of either type I or type II substrates. The hepatic microsomal mixed function oxidase might, however, be involved in the metabolism of circulating catecholamines under physiological conditions.