Cellular and subcellular localization of 3h-diethylstilboestrol in the central nervous system

The cellular and subcellular localization of radioactivity in the brain of immature female rats was determined by dry-mount autoradiography 2 h after iv injection of 1.0 microgram of (monethyl-3H) diethylstilboestrol per 100 g body weight. A specific topographic pattern of nuclear concentration of the synthetic oestrogen was obtained similar to that for 3H-oestradiol-17 beta in specific neurons of the basal hypothalamus, preoptic region and amygdala. In competition experiments, the nuclear concentration of radioactivity in all areas studied was inhibited by unlabeled oestradiol, while unlabeled testosterone had no effect. These data suggest that although oestradiol can bind to androgen receptors, the oestrogen receptor itself can account for the localization seen after the injection of 3H-oestradiol.