Journal Article

STEADY-STATE SERUM T^sub 3^ CONCENTRATIONS FOR 48 HOURS FOLLOWING THE ORAL ADMINISTRATION OF A SINGLE DOSE OF 3,5,3'-TRIIODOTHYRONINE SULFATE (T^sub 3^S)

Saponati, Giorgio, Rivolta, Giovanni, Santini, Ferruccio, Vitti, Paolo, Querci, Giorgia, Pinchera, Aldo, Braverman, Lewis E, Bussi, Simona, Bokor, Daniela, Ricco, Ilaria, Giannetti, Monica

2014

Overview

Sulfate conjugation of thyroid hormones is an alternate metabolic pathway that facilitates the biliary and urinary excretion of iodothyronines and enhances their deiodination rate, leading to the generation of inactive metabolites. A desulfating pathway reverses this process, and thyromimetic effects have been observed following the parenteral administration of 3,5,3'-triiodothyronine (T^sub 3^) sulfate (T^sub 3^S) in rats. The present study investigated whether T^sub 3^S is absorbed after oral administration in humans and if it represents a source of T^sub 3^. At all T^sub 3^S doses, serum T^sub 3^S concentrations increased, reaching a peak at 2 to 4 hours and progressively returning to basal levels within 8 to 24 hours. The T^sub 3^S maximum concentration and area under the 0- to 48-hour concentration-time curve were directly and significantly related to the administered dose. An increase in serum total T^sub 3^ concentration was observed, and the concentration increased further at 2 and 4 hours and then remained steady up to 48 hours after T^sub 3^S administration.

• Publisher: Elsevier Limited