Stimulation of Articular Chondrocytes of Middle-Aged Mice by a Cartilage-Bone Marrow Extract

Abstract

Articular chondrocytes of 1-year-old male mice of strain C₅₇B1 were stimulated by injections of a cartilage-bone marrow extract to undergo hypertrophy, intensified organellar development and hyperplasia. This response was attenuated as compared with that of growing animals treated similarly. The morphological findings are consistent with some increase in synthetic activity on the part of the chondrocytes. The increased cell death observed was attributed to overstimulation and subsequent exhaustion, and was considered responsible for the prominence of microscars in the matrix.