Metabolism of estrogens and their sulfates in rat uterine minces.

Abstract

Mature rat uterine minces were incubated with estrone, 17β-estradiol and their sulfates. Comparative incubations were made using immature uteri, uteri from ovariectomized animals, mature esophagus and immature esophagus. Hydrolysis of the 3-sulfate moiety was common in all experiments, although to varying extents. At the concentrations investigated (10−5–10−8M), there was nearly twice the uptake of the 3-sulfated estrogens by pooled mature uterine minces as was observed in the incubations with unconjugated estrogens. Whereas uteri obtained in the various stages of the estrous cycle concentrated 17β-estradiol-3-sulfate to the same extent, 17β-estradiol was taken up more readily by estrous than by proestrous or diestrous uteri. Although estrone and 17β-estradiol were interconverted in the mature uterus at the higher concentrations, only oxidation could be demonstrated at levels approaching the physiological state, and this varied throughout the cycle, being greatest at estrus. Oxidation was also demonstrate...