The Inactivation of Calcification in vitro

Abstract
It was possible to demonstrate the reversible inactivation of calcification in vitro of the hyper-trophic epiphyseal cartilage. When rachitic bone sections are shaken with strontium chloride or NaCl, calcification is inhibited. On subsequent shaking with CaCl2 solns., calcification takes place. In addition, inactivation takes place with 1/2 mE of cupric chloride in the presence of 150 mE of CaCl2. On subsequent snaking with 150 mE of CaCl2 (in the absence of cupric chloride) reactivation takes place. These expts. suggest that an essential step in mineralization is a reversible combination of Ca ion with some constituent of the bone cell, probably part of an enzyme system.