osteocyte
null · being built
| What it is | The bone cell embedded in the mineralised matrix, an osteoblast that was buried in the bone it made, wired to its neighbours by dendrites in canaliculi. |
|---|---|
| Comes from | Mesenchymal stromal cell |
| About | In the human femoral cortex osteocyte lacunae have a long axis peaking at 8 um and volumes peaking at 200 and 330 um3, with nearest neighbours 23 um apart and densities from 4 to 9 x 10^4 per mm3 across the osteon. |
| Source | Hannah KM, Thomas CD, Clement JG, De Carlo F, Peele AG. Bimodal distribution of osteocyte lacunar size in the human femoral cortex as revealed by micro-CT. Bone. 2010;47(5):866-71. PMID: 20691298 |
| Status | being built; its twin, knowledge and helper come with null |
Where it lives
| In lacunae in the lamellar bone of cortical osteons, denser toward the osteon's edge than near the Haversian canal | human · PMID 20691298 |
| In cortical and cancellous bone alike, mature and sclerostin-positive once embedded in mineralised matrix | human · PMID 16123173 |
What it does
| Forms a network of 42 billion cells and 3.7 trillion dendrites in the adult skeleton, 175,000 km of processes end to end | human · PMID 25708054 |
| Secretes sclerostin after embedding, limiting further bone formation by osteoblasts | human · PMID 16123173 |
| Is replenished at about 9.1 million cells a day by remodelling | human · PMID 25708054 |
What goes wrong
| Under glucocorticoid excess 28 percent of the osteocytes of metaphyseal cortical bone die by apoptosis, toward osteonecrosis | mouse and human · PMID 9664068 |