The metabolism of 17α-estradiol-3-glucoside and 17α-estradiol-3-glucuronoside in the rabbit

The injection of 17α-estradiol-6,7-3H-3-glucuronoside-U-14C into a rabbit led to the excretion of 17α-estradiol-3-glucuronoside-17-N-acetylglucosaminide with a 3H/14C ratio twice that of the injected material. When 17α-estradiol-6,7-3H-3-glucoside-U-14C was injected, the same double conjugate was excreted, completely devoid of 14C. This indicates that 50% of the injected glucuronoside is excreted without hydrolysis of the glycosidic bond, while the glucoside is completely hydrolyzed in vivo and the steroid reconjugated with glucuronic acid.