The Effect of Parathyroid Hormone and Vitamin D₃ Metabolites on CaBP Synthesis by Embryonic Duodenum, In Vitro

Abstract

Embryonic chick duodena were incubated, in vitro, for two days in the presence of vitamin D analogues and metabolites and the ability of PTH to potentiate the vitamin-D-dependent synthesis of CaBP measured. PTH potentiated CaBP synthesis in the presence of vitamin D₃, 25-OH-D₃, 1α-OH-D₃, DHT, and 1,25(OH)₂D₃. The synthesis of CaBP was directly related to the log of the medium PTH concentration over the range 1 × 10^-8 M to 5 × 10^-7M.

Vitamin D - Parathyroid Hormone - Calcium Binding Protein - Duodenum - Organ Culture