Characterization of rat iodothyronine sulfotransferases.

Sulfation appears to be an important pathway for the reversible inactivation of thyroid hormone during fetal development. The rat is an often used animal model to study the regulation of fetal thyroid hormone status. The present study was done to determine which sulfotransferases (SULTs) are important for iodothyronine sulfation in the rat, using radioactive T4, T3, rT3, and 3,3'-T2 as substrates, 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as cofactor, and rat liver, kidney and brain cytosol, and recombinant rat SULT1A1, -1B1, -1C1, -1E1, -2A1, -2A2, and -2A3 as enzymes.

Characterization of iodothyronine sulfatase activities in human and rat liver and placenta.

In conditions associated with high serum iodothyronine sulfate concentrations, e.g. during fetal development, desulfation of these conjugates may be important in the regulation of thyroid hormone homeostasis.