Osteoclast.jpg (500 × 333 pixels, file size: 41 KB, MIME type: image/jpeg)
Very large (up to 100 µm), multi-nucleated (about 5-10 visible in a histological section, but up to 50 in the actual cell) bone-resorbing cells.
- Cells arise by the fusion of monocytes (macrophage precursors in the blood) or macrophages.
- Osteoclasts attach themselves to the bone matrix and form a tight seal at the rim of the attachment site.
- The cell membrane opposite the matrix has deep invaginations forming a ruffled border.
- Osteoclasts empty the contents of lysosomes into the extracellular space between the ruffled border and the bone matrix.
- The released enzymes break down the collagen fibres of the matrix.
- Osteoclasts are stimulated by parathyroid hormone (produced by the parathyroid gland)
- Osteoclasts are inhibited by calcitonin (produced by specialised cells of the thyroid gland).
- Osteoclasts are often seen lying over the indentations of the bone matrix that are formed by their activity (resorption bays or Howship's lacunae).
- Bone Histology: Cartilage Histology | Histology Stains | Histology | cartilage | bone | bone timeline
Links: Histology | Histology Stains | Blue Histology images copyright Lutz Slomianka 1998-2009. The literary and artistic works on the original Blue Histology website may be reproduced, adapted, published and distributed for non-commercial purposes. See also the page Histology Stains.
Cite this page: Hill, M.A. (2020, July 4) Embryology Osteoclast.jpg. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/File:Osteoclast.jpg
- © Dr Mark Hill 2020, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G
Original File Name: Ocl41he.jpg
Click on a date/time to view the file as it appeared at that time.
|current||14:37, 18 February 2013||500 × 333 (41 KB)||Z8600021||increased image size and adjusted contrast.|
|11:28, 11 September 2009||300 × 200 (21 KB)||S8600021||Osteoclasts Very large (up to 100 µm), multi-nucleated (about 5-10 visible in a histological section, but up to 50 in the actual cell) bone-resorbing cells. They arise by the fusion of monocytes (macrophage precursors in the blood) or macrophages. Oste|