CORTICOSTEROID METABOLISM IN LIVER: STUDIES ON PERFUSED RAT LIVERS*

Abstract

Methods for extracting transformation products resulting from corticosteroid perfusion through isolated perfused rat livers are descr. The rate of transformation of cortisone, 17-hydroxycorticosterone, desoxycorticosterone, and 17-hydroxydesoxycorticosterone by perfused rat liver was detd. At corticosteroid levels of 10 mg. /100 ml. of blood, liver transforms about 100 [mu]g./min./g. of liver tissue. Upon recycling, when the initial substrate concn. has decreased and products of the initial reaction accumulate in the system, the initial rate of transformation declines to about 15-20 [mu]g./min./g. liver. Corticosteroid metabolism in isolated perfused rat livers appears to follow a basically similar pattern, with all of the corticoids studied. In all cases, the transformation products are, in the main, reduced compounds which no longer retain the [delta]^-3-ketone grouping. Of these, some retain the ketol side chain while others lose the characteristic side chain of corticoids.