Monensin inhibits collagenase production in osteoblastic cell cultures and also inhibits both collagenase release and bone resorption in mouse calvaria cultures.

Monensin, a monovalent cation ionophore, inhibited collagenase production in mouse osteoblast-rich bone cell and clonal osteogenic cell cultures. Inhibition of parathyroid hormone-stimulated bone resorption by monensin was also studied in calvaria cultures. Collagenase activity levels in the medium decreased concomitantly with the inhibition of bone resorption by monensin, indicating that monensin inhibited bone resorption by blocking collagenase secretion from osteoblasts in bone explants.