Effect of conjugation to glucose on the uptake of 17 beta-(6,7-3-H)estradiol by rabbit liver subcellular fractions.

Homogenates and nuclear fractions from rabbit liver were incubated with 17β-[6,7-³H] estradiol and with the 3-glucoside and 3-glucuronide of this steroid. Localization of 17β-estradiol in the cell nucleus was enhanced when the glucoside rather than the free steroid was incubated with homogenates. It is suggested that conjugation to glucose may facilitate the transport of the steroid into the liver cell, or may protect it from metabolism. The effect was not observed in uterine tissue fractions.