Continuous mechanical loading alters properties of mechanosensitive channels in G292 osteoblastic cells

Robert Davidson, P. A. Lingenbrink, L. A. Norton

Research output: Contribution to journalArticle

Abstract

G292 osteoblastic cells were cultured in dishes made with a flexible base of polytetrafluoroethylene (PTFE) and stretched (~1% strain level) continuously for 48 hours. Patch-clamp recording techniques were then used to monitor single channel currents of mechanosensitive ion channels in these cells. To stimulate mechanosensitive channels, we applied suction to the membrane, expressed as -cm Hg, directly through the patch pipette. GigaOhm seals were obtained on a total of 33 osteoblasts that contained a high- conductance (~180 pS) mechanosensitive channel, all in the cell attached configuration. Of these, 18 were obtained from cells that had been stretched for either 1 (n = 6), 24 (n = 4), or 48 (n = 8) hours, and 15 were obtained in control (nonstretched) cells at either 1 (n = 2), 24 (n = 5), or 48 (n = 8) hours. For unstrained cells, applied pressures ranging from -1 to -5 cm Hg increased the probability of channel opening (P(open)) from 0.05 ± 0.01 (mean + SEM) to 0.12 ± 0.07. By contrast, for the same values of applied pressure in stretched cells, P(open) ranged from 0.06 ± 0.01 to 0.49 ± 0.15. Our results suggest that intrinsic properties of mechanosensitive ion channels in the G292 osteoblastic cell may be modulated by continuous mechanical loading of the cell itself.

Original languageEnglish (US)
Pages (from-to)500-504
Number of pages5
JournalCalcified Tissue International
Volume59
Issue number6
DOIs
StatePublished - Dec 1996

Fingerprint

Ion Channels
Pressure
Suction
Polytetrafluoroethylene
Patch-Clamp Techniques
Osteoblasts
Cultured Cells
Membranes

Keywords

  • Ion channels
  • Mechanical loading
  • Osteoblast
  • Stretch-activation

ASJC Scopus subject areas

  • Endocrinology

Cite this

Continuous mechanical loading alters properties of mechanosensitive channels in G292 osteoblastic cells. / Davidson, Robert; Lingenbrink, P. A.; Norton, L. A.

In: Calcified Tissue International, Vol. 59, No. 6, 12.1996, p. 500-504.

Research output: Contribution to journalArticle

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