File:Osteoclast.jpg

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Osteoclast.jpg(500 × 333 pixels, file size: 41 KB, MIME type: image/jpeg)

Osteoclast

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 Development | Bone Development
Compact bone Compact canals | Compact lamellae | compact bone - low unstained | compact bone - high unstained | compact - low | compact - low | compact - med | compact - high |
Trabecular bone trabecular | lamellar | trabecular - overview HE | trabecular - low HE | trabecular - med HE
Endochondral ossification primary ossification | endochondral ossification
Intramembranous ossification intramembranous - VG low | intramembranous - VG high | intramembranous - HE low | intramembranous - HE high



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.


Original File Name: Ocl41he.jpg

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current14:37, 18 February 2013Thumbnail for version as of 14:37, 18 February 2013500 × 333 (41 KB)Z8600021 (Talk | contribs)increased image size and adjusted contrast.
11:28, 11 September 2009Thumbnail for version as of 11:28, 11 September 2009300 × 200 (21 KB)S8600021 (Talk | contribs)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
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