Species comparison of steroid UDP-glucuronyl transferase: correlation to TCDD sensitivity.

Estradiol glucuronidation via steroid UDP-glucuronyl transferase (sUDPGT) was examined in 2,3,7,8-te trachlorodibenzo-p-dioxin (TCDD) sensitive and resistant species and strains. Steroid UDPGT was not induced by treatment with TCDD or estradiol. The most sensitive species to TCDD lethality, the guinea pig, had relatively high steroid UDPGT activity, while the hamster, the most resistant species, and rats had low levels of activity; no differences in sUDPGT activities were observed between mouse or rat strains differing in susceptibility to TCDD intoxication. These results suggest a role for differences in steroid physiology in the determination of species susceptibility to TCDD, but also demonstrate that other factors are involved.