Abstract
Autoradiographic study using 3H-6-thymidine was carried out to investigate the effect of estrogen on the induction of DNA synthesis in uterine endometorium of ovaryectomized rats. Wistar strain rats weighing about 200 g were ovaryectomized, and 16 days later, a single dose of estradio1-17β was intramuscularly administered.
1) 3H-6-thymidine uptake by the endometorium after a single injection of 10 μg estradiol-17β was determined by in vivo and in vitro methods, and there was no difference between the two.
2) DNA synthesis was specifically increased in the surface epithelium after administration of estradiol-17β but no significant increase was observed both in stroma and glandular epithelium.
3) Change of the 3H-6-thymidine up take after a single injection of estradio1-17 β was examined, the maximum up take was detected 24 h after the injection.
4) A dose of 10 μg estradio1-17 β could induced the maximum up take of the labelled thymidine by the surface epithelium.
