Microscopic heat pulse-induced calcium dynamics in single WI-38 fibroblasts

• Itoh Hideki

  Department of Pure and Applied Physics, Graduate School of Advanced Science and Engineering, Waseda University Institute of Medical Biology, Agency for Science Technology & Research (A*STAR)

• Oyama Kotaro

  Department of Physics, Faculty of Advanced Science and Engineering, Waseda University

• Suzuki Madoka

  Waseda Bioscience Research Institute in Singapore (WABIOS) Organization for University Research Initiatives, Waseda University

• Ishiwata Shin’ichi

  Department of Pure and Applied Physics, Graduate School of Advanced Science and Engineering, Waseda University Department of Physics, Faculty of Advanced Science and Engineering, Waseda University Waseda Bioscience Research Institute in Singapore (WABIOS) Organization for University Research Initiatives, Waseda University

Abstract

Temperature-sensitive Ca²⁺ dynamics occur primarily through transient receptor potential channels, but also by means of Ca²⁺ channels and pumps on the endoplasmic reticulum membrane. As such, cytoplasmic Ca²⁺ concentration ([Ca²⁺]_cyt) is re-equilibrated by changes in ambient temperature. The present study investigated the effects of heat pulses (heating duration: 2 s or 150 s) on [Ca²⁺]_cyt in single WI-38 fibroblasts, which are considered as normal cells. We found that Ca²⁺ burst occurred immediately after short (2 s) heat pulse, which is similar to our previous report on HeLa cells, but with less thermosensitivity. The heat pulses originated from a focused 1455-nm infrared laser light were applied in the vicinity of cells under the optical microscope. Ca²⁺ bursts induced by the heat pulse were suppressed by treating cells with inhibitors for sarco/endoplasmic reticulum Ca²⁺ ATPase (SERCA) or inositol trisphosphate receptor (IP₃R). Long (150 s) heat pulses also induced Ca²⁺ bursts after the onset of heating and immediately after re-cooling. Cells were more thermosensitive at physiological (37°C) than at room (25°C) temperature; however, at 37°C, cells were responsive at a higher temperature (ambient temperature+heat pulse). These results strongly suggest that the heat pulse-induced Ca²⁺ burst is caused by a transient imbalance in Ca²⁺ flow between SERCA and IP₃R, and offer a potential new method for thermally controlling Ca²⁺-regulated cellular functions.

Journal

• BIOPHYSICS

  BIOPHYSICS 10 (0), 109-119, 2014

  The Biophysical Society of Japan

Keywords

• calcium imaging
• ER
• IR laser
• temperature change
• thermometer sheet

Details

• CRID: 1390282680197922176
• NII Article ID: 130004940803
• DOI: 10.2142/biophysics.10.109
• ISSN: 13492942
• Web Site: https://www.jstage.jst.go.jp/article/biophysics/10/0/10_109/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed