Collagenolytic Activity During Active Bone Resorption in Tissue Culture. ∗

Abstract

Summary

A tissue culture system has been used to study the release of collagenolytic activity from actively resorbing bone by measuring the degradation of purified, reconstituted H³-hydroxyproline- and H³-proline-labeled collagen fibrils. Under conditions where active bone resorption was observed morphologically, a collagenolytic factor was liberated from the bone which degraded reconstituted, undenatured collagen fibrils. This collagenolytic activity was increased by addition of parathyroid extract to the tissue culture medium, and still further enhanced when both parathyroid extract and heparin were added.