THE POSSIBLE RELATIONSHIP of hypercholesteremia to atherosclerosis had led to consideration of thyroxine as a useful agent in lowering serum cholesterol.1,3 Since the dose of L-thyroxine required for this purpose usually produces hypermetabolic effects,3 many analogues of thyroxine have been tested in an attempt to find one with a predominantly cholesterol-lowering action.4,5 This study was undertaken to determine the effect of oral dextrothyroxine (D-T4) on the metabolism of intravenously administered C14-labeled cholesterol and tripalmitin.
Materials and Methods
Twenty-two euthyroid male patients with high serum cholesterol levels, various arteriosclerotic disorders, or both were studied. No changes were made in any patient's program other than addition of the drug. The biological half-life of C 14-labeled cholesterol and tripalmitin in serum was determined for each patient for 30 days before and after the administration of 8 mg. of D-T4 daily. Respiratory quotient, oxygen uptake,