A STUDY OF 3-HYDROXY-3-METHYLGLUTARYL COENZYME A REDUCTASE ACTIVITY IN RAT PROSTATE

Abstract

The activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase, EC, 1. 1. 1. 34) was measured in rat ventral prostate and liver, in order to compare the regulation in both tissues. Hepatic microsomal HMG-CoA reductase activity in rat showed a diurnal variation and its peak was observed in mid dark period, as already reported by others. Prostatic microsomal HMG-CoA reductase activity had also a diurnal variation, but its peak point was at the transitional period from dark to light.
In castrated state and testosterone administration, HMG-CoA reductase activity showed respective different changes in both tissues. In rat liver, HMG-CoA reductase activity was elevated at 7 days after castration, but in the prostate, its activity showed no change. Subsequently, testosterone was administered in 7 days, the hepatic HMG-CoA reductase activity showed a slight supression, but the Prostatic HMG-CoA reductase activity was elevated. After castration, testosterone enanthate was administered for 3 weeks. The prostate weight was increased, but the peak of HMG-CoA reductase activity was observed after 7 days and after 21 days its activity showed the same level as the control.