Interaction of furosemide with serum thyroxine-binding sites: in vivo and in vitro studies and comparison with other inhibitors.

The diuretic furosemide inhibits serum protein binding of T4 in equilibrium dialysis, dextran-charcoal, and competitive ligand binding separation systems and displaces [125I]T4 from isolated preparations of T4-binding globulin (TBG), prealbumin, and albumin. Equilibrium dialysis studies of undiluted normal serum showed that about 10 micrograms/ml furosemide increased the free T4 and free T3 fractions. Displacement occurred at lower drug concentrations in sera with subnormal albumin and TBG levels.

Influence of urinary sodium on calcium excretion in normal individuals. A redefinition of hypercalciuria.

The twenty-four hour urinary excretion of calcium and sodium was measured in 38 normal volunteers after a week on a diet containing 400 mg of calcium per day. There was a significant correlation (P less than 0.001) between calcium and sodium excretion.