Steroidogenesis in Vitro by Homogenates of Adrenocortical Tissue of the European Eel (Anguilla anguilla L.)1

Abstract

Whole homogenates (10%) of eel adrenocortical tissue were incubated with cholesterol-7-3H and with mixtures of pregnenolone-16-3H +progesterone-4-14C and progesterone-l,2-3H + 17[alpha]-hydroxyprogesterone-4-14C. Cholesterol gave rise to tritiated cortisol and to a substance presumptively identified as pregnenolone-3H, while the 2 substrate pairs were partially transformed to tritium and carbon-14 labeled cortisol and 11-deoxycortisol. The presence of corticosterone, aldosterone or 18-hydroxycorticosterone could not be detected in either experiment. Analysis of the isotope content of the end-products suggested a relative lack of transformation of pregnenolone to progesterone. Quantitatively, the homogenate technique yielded transformation rates 100-fold higher than obtained by the use of adrenocortical tissue minces. It was concluded that, under these conditions, 11-deoxy cortisol is a metabolite in importance equal to cortisol.