THE METABOLISM OF [6-³H]1α, HYDROXYCHOLECALCIFEROL TO [6-³H]1α, 25-DIHYDROXYCHOLECALCIFEROL IN A PATIENT WITH RENAL INSUFFICIENCY

Abstract

To evaluate whether 1alpha-hydroxycholecalciferol is metabolized to 1alpha,25-dihydroxycholecalciferol in man, [6-3H]1alpha-hydroxycholecalciferol was given intravenously to a patient with renal failure who was maintained daily on 100,000 IU vitamin D and calcium supplements. Using Sephadex LH-20 and high-pressure liquid chromatography, it was clearly demonstrated that 1alpha-hydroxycholecalciferol rapidly disappears from the blood and is metabolized to 1alpha,25-dihydroxycholecalciferol.