41. *Osteoclasts are the cells responsible for bone resorption, thus they break down bone. 42. In space, however, there is an increase in osteoclast activity due to microgravity. 43. The brown tumors commonly associated with OFC display many of the same characteristics of osteoclasts . 44. Osteoclasts are generally present on the outer layer of bone, just beneath the periosteum.45. Upon partial dephosphorylation, both osteopontin and bone sialoprotein are incapable of binding to osteoclasts . 46. AE2 is required for normal osteoclast function. 47. Recent research suggests that kahweol may have beneficial effects on bone by inhibiting osteoclast differentiation. 48. Mantyh said the osteoclasts also seem to hypersensitize nerves which carry pain stimuli to the brain. 49. The osteoblast cell forms new bone, while osteoclast dissolves old and worn out bone tissue. 50. For example, the rate at which osteoclasts resorb bone is inhibited by calcitonin and osteoprotegerin.
