INHIBITION OF ADRENAL STEROID METABOLISM BY HEPARIN IN VIVO

Liver homogenates prepared from heparin pretreated female rats were assayed for cortisone A ring reducing activity. Heparin treatment had no apparent effect if an NADPH generating system was added to the homogenate, but in the absence of a generating system, cortisone reductase activity was clearly inhibited. When heparin was added to incubating liver slices, cortisone reduction by the slices or by homogenates prepared from them was inhibited. Heparin had an anti-inflammatory effect in the intact rat but not in the adrenalectomized animal. Heparin did, however, potentiate the anti-inflammatory action of cortisol in adrenalectomized rats. The intravascular half-life of corticosterone-4-14C was significantly prolonged after heparin administration. These results indicate that heparin can influence adrenal steroid metabolism in vivo. © 1968.