title: The effect of renal function on changes in circulating concentrations of 1,25-dihydroxycholecalciferol after an oral dose.
abstract: 1. 1,25- Dihydroxycholecalciferol [1,25-(OH)2D3] was administered orally to four normal subjects and six patients with chronic renal failure not on dialysis. The serum concentration of 1,25-(OH)2D3 was measured by radioimmunoassay in both groups from samples taken before, and at regular intervals up to 48 h after, the oral dose. 2. The plasma half-time for the disappearance of the administered 1,25-(OH)2D3 was estimated by determining the time for a 50% reduction from the peak increment of the sterol. In normal subjects the calculated value ranged from 5 to 8 h compared with 18 to 44 h in uraemic patients. 3. It appears from our studies that in uraemic subjects there is impaired ability to metabolize or excrete 1,25-(OH)2D3.
mesh_terms: D000328:Adult; D002117:Calcitriol / Q000097:blood*; D006207:Half-Life; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D008297:Male; D014511:Uremia / Q000097:blood
chemical_list: D002117:Calcitriol