Osteocyte Mechanosensation and Transduction


Osteocytes are the major bone cell composing over 90-95% of all adult bone cells. These cells with their long dendritic processes, their connectivity and strategically placed locations within the mineralized bone matrix suggest that they are mechanosensory cells. They are ideally situated to sense mechanical loading to the skeleton and to transmit signals within their osteocyte network and to cells on the bone surface. These cells have been shown to be exquisitely sensitive to mechanical loading in the form of fluid flow shear stress with the early release of small signaling molecules such as nitric oxide, ATP, and prostaglandin. These cells also send later signals in the form of proteins in response to shear stress. As the microenvironment surrounding the osteocyte changes with disease and with age, these changes may influence how this cell senses and responds to mechanical loading. Key observations and concepts surrounding mechanosensation and transduction in this cell type are highlighted and emphasize the need for more information regarding osteocyte function.


Primary Cilium Hypophosphatemic Rickets Dentin Matrix Protein Mechanosensory Cell Bone Fluid 



The author’s work in osteocyte biology is supported by the National Institutes of Health AR-46798.


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Authors and Affiliations

  1. 1.Department of Oral BiologyUniversity of Missouri at Kansas City School of DentistryKansas CityUSA

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