Details

Autor(en) / Beteiligte

• Britz, Hayley M
• Carter, Yasmin
• Jokihaara, Jarkko
• Leppänen, Olli V
• Järvinen, Teppo L.N
• Belev, George
• Cooper, David M.L

Titel

Prolonged unloading in growing rats reduces cortical osteocyte lacunar density and volume in the distal tibia

Ist Teil von

• Bone (New York, N.Y.), 2012-11, Vol.51 (5), p.913-919

Ort / Verlag

Amsterdam: Elsevier Inc

Erscheinungsjahr

2012

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Abstract Bone dynamically adapts its structure to the environmental demands placed upon it. Load-related stimuli play an important role in this adaptation. It has been postulated that osteocytes sense changes in these stimuli and initiate adaptive responses, across a number of scales, through a process known as mechanotransduction. While much research has focused on gross and tissue-level adaptation, relatively little is known regarding the relation between cellular-level features (e.g. osteocyte lacunar density, volume and shape) and loading. The increasing availability of high resolution 3D imaging modalities, including synchrotron-based techniques, has made studying 3D cellular-level features feasible on a scale not previously possible. The primary objective of this study was to test the hypothesis that unloading (sciatic neurectomy) during growth results in altered osteocyte lacunar density in the tibial diaphysis of the rat. Secondarily, we explored a potential effect of unloading on mean lacunar volume. Lacunar density was significantly (p < 0.05) lower in immobilized bones (49,642 ± 11,955 lacunae per mm3 ; n = 6) than in control bones (63,138 ± 1956 lacunae per mm3 ; n = 6). Mean lacunar volume for immobilized bones (209 ± 72 μm3 ; n = 6) was significantly smaller (p < 0.05) than that for the control bones (284 ± 28 μm3 ; n = 6). Our results demonstrate that extreme differences in loading conditions, such as those created by paralysis, do indeed result in changes in osteocyte lacunar density and volume. Further investigation is warranted to examine relations between these measures and more subtle variation in loading as well as pathological states, which have been linked to alterations in mechanotransduction.