Effect of Cyclic Hydraulic Pressure on Osteocytes

INTRODUCTION: Although bone is known to respond to various forms of mechanical loading including substrate strain, fluid shear, and interstitial fluid pressure, the latter receives relatively little attention. . Macroscopically, venous stasis or applied pressurization by external loading was associated with increased bone formation.. At the cellular level, osteoblasts have been shown to respond to hydraulic pressure. However, understanding of the response of osteocytes to changes of fluid pressure in bone is limited. Osteocytes, bone cells embedded in the calcified matrix, are believed to be the mechanosensors and responsible for orchestrating the bone remodelling process. It was estimated that osteocytes experience cyclic hydraulic pressure (CHP) up to 0.27 MPa under physiological conditions. In this study, we investigate changes in several key intracellular events when osteocytes are subjected to CHP. We hypothesize that osteocytes are able to sense CHP, and respond by significant changes in the level of intracellular calcium concentration ([Ca]i)., apoptosis, and gene expression of several key regulators of bone remodeling.