Human uterine endometrium and endometriotic tissue transplanted into nude mice. Morphologic effects of various steroid hormones.

In a study of the morphologic effects of various steroid hormones on human uterine endometrium and endometriotic tissue, specimens from 6 women were transplanted subcutaneously into 24 nude mice. In each case, specimens collected simultaneously were transplanted to 4 mice, endometrium to one lateral abdominal wall and endometriotic tissue to the other. All mice were given polyestradiol phosphate subcutaneously the first day after operation. After a 2-week interval, of each 4 mice, 1 mouse was given polyestradiol phosphate, 1 medroxyprogesterone acetate, 1 danazol, and 1 no further injections. This treatment continued for 8 weeks, after which the mice were killed and the grafts extirpated. Histologic changes in the grafts varied according to the treatment schedule but were very similar in both types of tissue. Our findings suggest that histologic differences between endometrium and endometriotic tissue seen under natural conditions may, at least partly, be due to variations in environmental factors.