Albumin is responsible for the transport of 25-hydroxycholecalciferol in the Capuchin monkey. This was confirmed by gel filtration, analytical polyacrylamide-disc-gel electrophoresis, polyacrylamide-gel isoelectric focusing and a competitive protein-binding assay. Association constants of the serum transport proteins of a New and an Old World monkey towards 25-hydroxycholecalciferol were calculated; the transport protein in the New World monkey has a lower affinity for the vitamin D metabolite than the transport protein in the Old World primate.
