Serum estrogens and gonadotropins in developing androgenized and normal female rats.

Serum levels of estradiol and estrone in normal female rats were compared with those in females treated with 50 mcg testosterone propionate on Day 5 postpartum and correlated with gonadotropin levels. The hormones were measured by radioimmunoassay following purification of the estrogens by column chromatography. Estradiol and estrone declined in normal rats between Days 10 and 20. Estradiol increased (p less than .01) between Days 25 and 30 but estrone remained constant. Androgenized rats had about 3 times more estradiol and estrone as the normals on Day 10 (p less than .01). Both hormones decreased and then increased to about 15 times the normal values by Day 20. At 30 days the normals had about the same amount of estradiol as the androgenized rats. However, estrone was higher (p less than .01) in the normals. Estradiol levels were similar in older than 40 days androgenized and normal rats on the morning of proestrus. In rats who were ovariectomized prior to androgen injection, estradiol was higher (p less than .01) than in normals but lower (p less than .01) than in intact androgenized rats. Estrone was similar to intact androgenized rats but higher than in normals. Follicle stimulating hormone and luteinizing hormone were higher in normal females at 10 and 15 days (p less than .01). At 30 days the differences were small. Prolactin levels were similar until Days 20-25 when they increased in both (significantly in the androgenized, p less than .01). It was concluded that estrogens play a role in producing and rogenized female rats and that gonadotropins may be involved in androgenization. hypothalamic changes in androgenized female rats and that gonadotropins may be involved in androgenization.