Where does osteoclast develop from?
bone marrow
Osteoclasts are multinucleated cells that derive from hematopoietic progenitors in the bone marrow which also give rise to monocytes in peripheral blood, and to the various types of tissue macrophages. Osteoclasts are formed by the fusion of precursor cells.
What is the structure of osteoclast?
Osteoclasts are multinucleated giant cells showing specialized membrane structures, clear zones and ruffled borders, which are responsible for the process of bone resorption.
What does the osteoclast do?
Osteoclasts are the cells that degrade bone to initiate normal bone remodeling and mediate bone loss in pathologic conditions by increasing their resorptive activity. They are derived from precursors in the myeloid/monocyte lineage that circulate in the blood after their formation in the bone marrow.
Where is the osteoclast found?
OSTEOCLASTS are large cells that dissolve the bone. They come from the bone marrow and are related to white blood cells. They are formed from two or more cells that fuse together, so the osteoclasts usually have more than one nucleus. They are found on the surface of the bone mineral next to the dissolving bone.
What hormone stimulates osteoclast activity?
Parathyroid hormone (PTH)-related protein is a potent stimulator of osteoclast-like multinucleated cell formation to the same extent as PTH in mouse marrow cultures.
What causes increased osteoclast activity?
Low levels of calcium stimulates the release of parathyroid hormone (PTH) from chief cells of the parathyroid gland. In addition to its effects on kidney and intestine, PTH increases the number and activity of osteoclasts.
How is osteoclast formed in rheumatoid arthritis?
A possible mechanism of osteoclast formation by activated T cells in rheumatoid arthritis. Activated T cells present in the synovial tissues also produce membrane-associated RANKL, some of which are cleaved enzymatically from the plasma membrane, resulting in soluble RANKL (sRANKL).
Which is a factor that induces osteoclastogenesis?
RANKL, which is induced by bone resorbing factors such as 1-α,25 (OH) 2 D 3, parathyroid hormone (PTH) and IL-11 on the plasma membrane of osteoblasts/stromal cells, binds its receptor RANK present in osteoclast progenitors and mature osteoclasts.
How are osteoclasts different from macrophage polykaryons?
Osteoclasts are large multinucleated giant cells that express tartrate-resistant acid phosphatase (TRAP) activity and calcitonin receptors, and they have the ability to form resorption pits on bone and dentine slices. The characteristics of osteoclasts thus differ from those of macrophage polykaryons.