Ipodate and 8-anilino-1-naphthalene sulfonic acid block receptor binding of T3 in rat liver.

We have determined that 8-anilino-1-naphthalene sulfonic acid (ANS) and ipodate are effective inhibitor in vitro of 125I-T3 binding to rat hepatic nuclei receptors. Both of these agents are estimated to have a Kd for the T3 receptor of about 1--2 x 10(-4) M. Indirect preliminary studies suggest that ANS is a non-competitive inhibitor and ipodate is a competitive inhibitor of T3 binding. Compounds such as tyropanoate and diatrizoate and iodide had no effect on T3 receptor binding. Further in vivo studies with ipodate suggested that T3 receptor binding inhibition also occurred when ipodate was given intravenously to rats.