Comparative kinetic study of the binding between 2,3,7,8‐tetrachlorodibenzo‐ρ‐dioxin and related ligands with the hepatic Ah receptors from several rodent species

Kinetic analysis of the time course of association of [³H]‐2,3,7,8‐tetrachlorodibenzo‐ρ‐dioxin with hepatic cytosoi from five rodent species gave additional evidence for differences in the properties of the Ah receptor ligand binding subunit between species. A parallel study of the association of six tritiated polychlorinated dibenzopρ‐dioxins and dibenzofurans with hepatic Ah receptor from Wistar rat and C57BL/6 mouse showed that their rank order for kinetic affinity did not correlate with the rank ordering of their toxic potency‐ and may vary according to the source of the Ah receptor.