中文摘要：

破骨细胞一直被认为是一种仅在骨重建中发挥骨吸收作用的细胞，然而，近几年这一观点已彻底改变。这种多核细胞在体内具有复杂的生物学功能。除了能够吸收钙化的骨基质以外，破骨细胞在骨形成、骨组织血管形成、关节软骨生理病理过程、免疫和代谢调节中均发挥着重要作用。

英文摘要：

The osteoclast has been considered as a cell with the exelusive function of bone remodel- ling. However, this concept has been changed drastically according to the advances in the last few years. These multinuclear cells play multifunctional role in vivo. In addition to its ability of reab- sorbing the calcified bone matrix, the osteoclast plays important role in bone formation, angiogene- sis, physiology and pathology of cartilage, immunological regulation and metabolic modulation.