ABSTRACT
The tissue distribution of estrogen receptor alpha (ERα) and progesterone receptor (PR) was examined using immunohistochemical technique. Image analysis was done to quantify the immune reactivity. The ERα and PR was localized in luminal epithelium, glandular epithelium, stromal cells, endothelial cells and myometrium and few cells in perimetrium. The immuno staining was observed in the nuclei of cells, however, faint cytoplasmic staining for PR was also observed. Variations were seen in the different tissue compartments of the uterus and during the different phases of the estrous cycle. Significantly higher number of ERα positive cells was observed in lamina epithelialis as compared to stromal cells and smooth muscle cells in myometrium. Significantly higher percentage of ERα positive cells was observed in the lamina epithelialis and lining epithelium of endometrial glands during follicular phase as compared to the luteal phases of estrous cycle (P < 0.05). Higher number of PR positive cells was observed in lamina epithelialis as compared to stromal cells and smooth muscle cells in myometrium (P < 0.05). Higher percentage of PR positive cells was observed in the lamina epithelialis during follicular phase as compared to the luteal phases of estrous cycle (P < 0.05). There was no significant difference in the immuno reactivity in stromal cells, lining epithelium of endometrial glands and smooth muscle cells of myometrium during the phases of estrous cycle. The study concluded that ERα and PR expressions were higher during follicular phase as compared to the luteal phase