Abstract
This study was designed to investigate the effect of estrogen(Est) on the progestcrone(Prog) target cells by autoradiography. The spayed 16 mice(ICR, approximately 18~25g) were randomly alloted into 3 groups. $^3H$-Prog-treated group were injected with $40{\mu}Ci$ of $^3H$-Prog/mouse/day for 1 day, Est + $^3H$-Prog-treated group with $20{\mu}Ci$ of $17{\beta}$-Est/mouse/day for 3 days and then with $40{\mu}Ci$ of $^3H$-Prog/mouse at 4th day, and Est+$^3H$-thymidine(TdR)-treated group with $20{\mu}g$ of $17{\beta}$-Est/mouse/day for 3 days and then $80{\mu}Ci$ of $^3H$-TdR/mouse at 4th days. 1. Mice uteri of both Est+$^3H$-Prog-treated group and Est+$^3H$-TdR-treated group were hypemophied in gross finding and the endometrium and myometrium were thickened in microscopic findings. These findings were confirmed that Est enlarged the uteri of mice. 2. Cryo-preparations of mice organs were processed for autoradiography using Kodak NTB-2 emulsion following Kodak D-19 developer and hematoxylin counterstain. In each group, the number values of silver grain distribution appeared to be higher in the $^3H$-Prog-treated group than in the Est+$^3H$-Prog-treated group. It was considered that Est and Prog inhibit each other in action. 3. In both $^3H$-Prog-treated group and Est+$^3H$-Prog-treated group, the uteri have highest distribution rates of silver grains than in other organs, and the cerebral neurons, hepatocytes, bronchiolar epithelial cells and splenic reticular cells also contained some silver grains. 4. The orders of the cell types with more number of silver grains in the uteri were stromal cells, glandular epithelial cells, luminal surface cells and muscular cells and also were as above orders in distribution of proliferating cell type by $^3H$-TdR.