Estrogen-induced Increase in Eosinophil Number and Peroxidase Activity in Uterus of Genetically Mast Cell-deficient W/WV Mice1

The role of mast cells in induction of uterine eosinophilia was investigated by using genetically mast cell-deficient (WB X C57BL/6)F1-W/Wv (hereafter called WBB6F1-W/Wv) mice. The injection of estradiol-17 beta (0.16 micrograms/g body weight) increased the peroxidase activity and eosinophil number in the uteri of castrated WBB6F1-W/Wv and WBB6F1-+/+ mice. Since no significant differences were detectable between these two type of mice, mast cells did not seem to be essential for the estrogen-induced uterine eosinophilia, at least in mice.