Metabolism of Tritiated 25-Hydroxycholecalciferol in Chronically Uremic Children Before and After Successful Renal Homotransplantation

Abstract

Immunoreactive parathyroid hormone (IrPTH) concentrations and the metabolism of 3H-25-hydroxycholecalciferol (3H-25-OHD3) were examined in 2 children with chronic renal failure before and after successful transplantation. Before transplantation, IrPTH concentrations were markedly elevated and the conversion of 3H-25-OHD3 to 3H-1,25-(OH)2D3 was impaired. Successful renal transplantation resulted in a fall in IrPTH and the ability to generate 3H-1,25-(OH)2D3 from 3H-25-OHD3. These changes were observed despite insignificant differences in circulating 25-OHD3 in the pre- and post-transplantation periods.