Open AccessDistinct intracellular calcium responses of individual cultured human keratinocytes to air pressure changes
Author(s) -
Ikeyama Kazuyuki,
Nakatani Masashi,
Kumamoto Junichi,
Denda Mitsuhiro
Publication year - 2013
Publication title -
skin research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.521
H-Index - 69
eISSN - 1600-0846
pISSN - 0909-752X
DOI - 10.1111/srt.12045
Subject(s) - calcium , keratinocyte , chemistry , human skin , intracellular , calcium in biology , cell culture , biophysics , microbiology and biotechnology , biology , biochemistry , in vitro , organic chemistry , genetics
Background We previously showed that application of hydraulic pressure to cultured human keratinocytes induced elevation of intracellular calcium concentration ([Ca 2+ ] i ), but the absolute value of the pressure could not be determined. Purpose To evaluate the effect of the absolute value of pressure on keratinocytes and other skin cells. Methods In the present work, we examined the effect of changes in absolute pressure level by observing the [Ca 2+ ] i responses of cultured human keratinocytes and other cells cultured at the bottom of a hermetically sealed plastic flask as the air pressure in the flask was increased gradually, held stable, and then decreased abruptly, using the Ca 2+ ‐indicator fura‐2. Results We found that the [Ca 2+ ] i of differentiated keratinocytes was changed significantly in each phase, whereas undifferentiated keratinocytes and other cells derived from skin or dorsal root ganglion showed no response. Removal of calcium from the medium blocked the increase in [Ca 2+ ] i in differentiated keratinocytes. The [Ca 2+ ] i responses of individual differentiated keratinocytes in the increasing, stable and decreasing phases of pressure change varied from cell to cell. The threshold of air‐pressure increase from the original level for inducing [Ca 2+ ] i response was 5 – 20 hP a. Conclusion These results suggest that epidermal keratinocytes might contain a sensory system that detects changes of external pressure on the skin.