“A concentration as low … 10(-10) M retinoic acid shifted the … of both T4 and T3 so that the concentration of each associated with maximal enzyme stimulation was 10(-9) M instead …(-10) M. Retinoic acid displaced [125I]T4 binding to red cell membranes as effectively as unlabeled T4.”
“These results indicate that retinoic acid can partially block the T4 and T3 stimulation of Ca2+-ATPase in human red cell membranes and suggest a physiologic role for the retinoid as a modulator of this peripheral action of thyroid hormone.”