Abstract
Osteoblasts sense and respond to mechanical stimuli in a process involving influx and release of large ions and signaling molecules. Unapposed gap junction hemichannels formed of connexin43 (Cx43) have been proposed as a major route for such exchange, in particular for release of ATP and prostaglandin E 2 (PGE2) in osteocytes. However, we have found that Cx43-null osteoblasts have unaltered, mechanically induced PGE2 release and ATP-induced YoPro dye uptake. In contrast, PGE2 release in response to fluid shear stress is abolished in P2X7 receptor (P2X7R)-null osteoblasts, and ATP-induced dye uptake is attenuated following treatment of wild-type cells with a P2X7R or Pannexin1 (Panx1) channel blocker. These data indicate that Panx1 channels, in concert with P2X7R, likely form a molecular complex that performs the hemichannel function in osteoblast mechanosignaling.
Original language | English (US) |
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Pages (from-to) | 401-409 |
Number of pages | 9 |
Journal | Journal of Membrane Biology |
Volume | 245 |
Issue number | 7 |
DOIs | |
State | Published - Jul 2012 |
Keywords
- ATP
- Dye uptake
- Gap junction
- Osteoblast
- P2XR
ASJC Scopus subject areas
- Biophysics
- Physiology
- Cell Biology