Osteocalcin is a major noncollagenous protein component of bone extracellular matrix,
synthesized and secreted exclusively by osteoblastic cells in the late stage of maturation,
and is considered indicator of osteoblast differentiation. Osteocalcin expression is
modulated by parathyroid hormone (PTH) and a variety of other factors. The cAMP-
dependent protein kinase pathway has been shown previously to have an essential role in
PTH signaling and regulation of osteocalcin expression. To determine the extent to which …