Evidence for a Vitamin D 3 -Induced Calcium-Binding Protein in New World Primates 1

Summary

The evidence presented indicates that two species of new world monkeys, the cebus and the squirrel, are capable of synthesizing an intestinal calcium-binding factor in response to vitamin D₃ supplementation. Vitamin D₃ increased the calcium-binding activity of supernatant fluid of intestinal homogenates. The binding activity was partially purified by gel filtration chromotography. Acrylamide gel electrophoresis also showed a unique protein-staining band in the fluid from vitamin D³-treated monkeys which was not present in the untreated animals. The monkey binding factor appears analogous to the vitamin D-induced calcium-binding proteins identified in other species.