Regulation of the β2-adrenergic receptor and its mRNA in the rat ventral prostate by testosterone

AbstractTo investigate the regulation of β2AR expression in rat ventral prostate the effects of castration and testosterone replacement on the β2AR were studied by ligand binding and Northern blot analysis. Orchidectomy depressed β2AR number by 50% within 4 days and testosterone administration to 4-day castrates produced a rapid and complete recovery of β2AR number within 24 h. In contrast to receptor number, β2AR mRNA levels did not change relative to total RNA following castration. However, during the testosterone replacement period β2AR mRNA levels rose transiently, reaching a maximum (3.5-fold) between 8 and 12 h, and this increase in mRNA preceded the recovery in β2AR number in the membrane. Regulation of β2AR gene expression by testosterone in the ventral prostate is thus complex and probably involves both transcriptional and post-transcriptional components