Calcification XVIII. Lack of Correlation between Calcification in vitro and Glycolytic Enzymes.

Summary (1) Glycolytic enzymes and their relation to in vitro calcification of the preosseous cartilage of rachitic rat bone tissue have been studied. The findings indicate that although glycolytic enzymes are present in deep frozen tissue, ability to calcify in vitro is lost. However, if the tissue is treated first with calcium chloride and then stored in the deep freeze, the glycolytic enzymes are either absent or present only in trace amounts while the calcifying mechanism remains virtually intact. (2) Bone sections heated at 65°C and then treated with calcium chloride retain their ability to calcify in vitro despite the destruction of the glycolytic enzymes during the heating process. (3) Demineralization of bones results in a loss of glycolytic enzyme activity. However, when the demineralized bones are treated with chondroitin sulfate and then with calcium chloride, the calcifying mechanism is restored but not the glycolytic enzyme activity. (4) It is concluded that glycolytic enzymes are not part of the minimal system required for calcification.