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. 1988 Jul;54(1):187–190. doi: 10.1016/S0006-3495(88)82944-8

Stretch-activated cation channels in human fibroblasts.

L L Stockbridge 1, A S French 1
PMCID: PMC1330329  PMID: 2458140

Abstract

Nonconfluent fibroblasts are relatively depolarized when compared with confluent fibroblasts, and transient hyperpolarizations result from a range of external stimuli as well as internal cellular activities. This electrical activity ceases, along with growth and mitogenic activity, when the cells become confluent. A calcium-activated potassium conductance is thought to be responsible for these hyperpolarizations, but in human fibroblasts the large calcium-activated potassium channel is not stretch-activated. We report here the identification of single stretch-activated cation channels in human fibroblasts, using the cell-attached and inside-out patch clamp techniques. The most prominent channel had a conductance of approximately 60 pS (picoSeimens) in 140 mM potassium and was permeable to potassium and sodium. The channel showed significant adaptation of activity when stretch was maintained over a period of several seconds, but a static component persisted for much longer periods. Higher conductance channels were also observed in a few excised patches.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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