Page 285 - Atlas of Histology with Functional Correlations

helical course

Osteocytes in lamellar bone are arranged around the central canal

BONE CELLS AND THEIR FUNCTION

Osteoprogenitor Cells

Osteoprogenitor cells are derived from mesenchyme and are located in the
inner layer of periosteum, endosteum, osteons, and perforating canals

Osteoprogenitor cells differentiate into osteoblasts

Osteoblasts

Osteoblasts are on the bone surfaces and synthesize the osteoid matrix with

collagen fibers and different glycoproteins
Osteoblasts release matrix vesicles that form hydroxyapatite and calcification
of osteoid
Osteoblasts produce RANKL (receptor for activation of nuclear factor-kappa

B ligand)
M-CSF (monocyte colony–stimulating factor) produced by osteoblasts is
needed for osteoclast formation

Osteocytes

Osteocytes are mature osteoblasts, are located in lacunae, and use canaliculi
for communication and exchange of metabolic products and nutrients

Osteocytes maintain homeostasis of bone and blood concentrations of
calcium and phosphate

Osteoclasts

Osteoclasts are multinucleated phagocytic cells responsible for resorption,
remodeling, and bone repair
Belong to the mononuclear macrophage–monocyte cell line and are found in
enzyme-eroded depressions (Howship lacunae)
Activity influenced by parathyroid hormone and calcitonin

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