The osteoclast-endothelium interface during bone resorption in the femurs of young rabbits.

The morphological between the osteoclasts at the endosteal surface of two-week-old rabbit femurs and the endothelium of vascular channels of the bone marrow was examined. Light microscopy revealed that 85% of the osteoclasts make direct contact with the endothelial cells. The ultrastructure of this osteoclast-endothelium interface shows that the osteoclast has specialized processes which reach towards the endothelial cells coming into proximity with them. On rare occasions, specialized junctions between these processes and the endothelial cells are noted.