|
|
||||||||
Department of Bioengineering, University of California, San Diego, La Jolla, California 92093
Bone cells are subject to interstitial fluid flow (IFF) driven by venous pressure and mechanical loading. Rapid dynamic changes in mechanical loading cause transient gradients in IFF. The effects of pulsatile flow (temporal gradients in fluid shear) on rat UMR106 cells and rat primary osteoblastic cells were studied. Pulsatile flow induced a 95% increase in S-phase UMR106 cells compared with static controls. In contrast, ramped steady flow stimulated only a 3% increase. Similar patterns of S-phase induction were also observed in rat primary osteoblastic cells. Pulsatile flow significantly increased relative UMR106 cell number by 37 and 62% at 1.5 and 24 h, respectively. Pulsatile flow also significantly increased extracellular signal-regulated kinase (ERK1/2) phosphorylation by 418%, whereas ramped steady flow reduced ERK1/2 activation to 17% of control. Correspondingly, retinoblastoma protein was significantly phosphorylated by pulsatile fluid flow. Inhibition of mitogen-activated protein (MAP)/ERK kinase (MEK)1/2 by U0126 (a specific MEK1/2 inhibitor) reduced shear-induced ERK1/2 phosphorylation and cell proliferation. These findings suggest that temporal gradients in fluid shear stress are potent stimuli of bone cell proliferation.
shear stress; pulsatile fluid flow; osteoblasts
This article has been cited by other articles:
![]() |
Y. Korkmaz, W. Bloch, D. Steinritz, M.A. Baumann, K. Addicks, K. Schneider, and W.H.-M. Raab Bradykinin mediates phosphorylation of eNOS in odontoblasts. J. Dent. Res., June 1, 2006; 85(6): 536 - 541. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. C. Riddle, A. F. Taylor, D. C. Genetos, and H. J. Donahue MAP kinase and calcium signaling mediate fluid flow-induced human mesenchymal stem cell proliferation Am J Physiol Cell Physiol, March 1, 2006; 290(3): C776 - C784. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. R. White, H. Y. Stevens, M. Haidekker, and J. A. Frangos Temporal gradients in shear, but not spatial gradients, stimulate ERK1/2 activation in human endothelial cells Am J Physiol Heart Circ Physiol, December 1, 2005; 289(6): H2350 - H2355. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Shiratsuchi and M. D. Basson Activation of p38 MAPK{alpha} by extracellular pressure mediates the stimulation of macrophage phagocytosis by pressure Am J Physiol Cell Physiol, May 1, 2005; 288(5): C1083 - C1093. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hughes-Fulford Signal Transduction and Mechanical Stress Sci. Signal., September 7, 2004; 2004(249): re12 - re12. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-W. Ni, H.-J. Hsieh, Y.-J. Chao, and D. L. Wang Interleukin-6-induced JAK2/STAT3 signaling pathway in endothelial cells is suppressed by hemodynamic flow Am J Physiol Cell Physiol, September 1, 2004; 287(3): C771 - C780. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Ponik and F. M. Pavalko Formation of focal adhesions on fibronectin promotes fluid shear stress induction of COX-2 and PGE2 release in MC3T3-E1 osteoblasts J Appl Physiol, July 1, 2004; 97(1): 135 - 142. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Shiratsuchi and M. D. Basson Extracellular pressure stimulates macrophage phagocytosis by inhibiting a pathway involving FAK and ERK Am J Physiol Cell Physiol, June 1, 2004; 286(6): C1358 - C1366. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |