Esterase XXV. On the induction of Es-9 esterase of mouse kidney by testosterone.

The Es-9 esterase is expressed in the cortical zone of the NMRI mouse kidney only in the presence of testosterone. In disc electrophoresis, three esterase bands, absent in the control, emerge under the influence of exogenous testosterone, accompanied by the appearance of active sites, as shown by marking with [3H] diisopropyl fluorophosphate ([3H]DFP). It is suggested that the testosterone dependent appearance of Es-9 activity is due to true enzyme induction which requires the presence of an intact testosterone receptor.