Analytical Sciences

Abstract − Analytical Sciences, 18(11), 1205 (2002).

Single-Cell Imaging of the Ca2+ Influx into Bovine Endothelial Cells Occurring in Response to an Alternating Electric Stimulus
Hideaki MATSUOKA,* Kenji HASHIMOTO,* Shigetoshi HORIKIRI,* Mikako SAITO,* Kimiko YAMAMOTO,** and Joji ANDO**
*Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
**Department of Biomedical Engineering, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
The electric control of cellular functions via Ca2+ was formerly suggested. From this viewpoint, the involvement of a Ca2+ channel was studied using bovine fetal arterial endothelial (BFAE) cells in which P2X4, an ATP-operated and fluid shear stress sensitive Ca2+ channel, exists predominantly. An electric stimulus (sine wave, 10 Hz, 10 VPP, 30 s) caused a marked influx of Ca2+ into BFAE cells from an extracellular solution. The magnitude of the [Ca2+]i change increased with a decrease in the frequency in the range from 100 Hz to 5 Hz. Regarding the pathway of this Ca2+ influx, single-cell imaging and an ATP depletion experiment strongly suggested the involvement of a pathway different from P2X4. This pathway was thought to be a non-specific one, because typical Ca2+ channel blockers, such as verapamil, Gd3+, and Co2+, could not inhibit the Ca2+ influx.