Nanosecond-duration electric stimuli are distinguished by the ability to permeabilize intracellular membranes and recruit Ca2+ from intracellular stores. We quantified this effect in non-excitable cells (CHO) using ratiometric Ca2+ imaging with Fura-2. In a Ca2+-free medium, 10-, 60-, and 300-ns stimuli evoked Ca2+ transients by mobilization of Ca2+ from the endoplasmic reticulum. With 2 mM external Ca2+, the transients included both extra- and intracellular components. The recruitment of intracellular Ca2+ increased as the stimulus duration decreased. At the threshold of 200–300 nM, the transients were amplified by calcium-induced calcium release. We conclude that nanosecond stimuli mimic Ca2+ signaling while bypassing the usual receptor- and channels mediated cascades. The recruitment of the intracellular Ca2+ can be controlled by the duration of the stimulus.
Original Publication Citation
Semenov, I., Xiao, S., Pakhomova, O. N., & Pakhomov, A. G. (2013). Recruitment of the intracellular Ca2+ by ultrashort electric stimuli: The impact of pulse duration. Cell Calcium, 54(3), 145-150. doi:10.1016/j.ceca.2013.05.008
Semenov, Iurii; Xiao, Shu; Pakhomova, Olga N.; and Pakhomov, Andrei G., "Recruitment of the Intracellular Ca2+ By Ultrashort Electric Stimuli: The Impact of Pulse Duration" (2013). Bioelectrics Publications. 203.
0000-0002-0302-1355 (Semenov), 0000-0002-0375-8373 (Xiao), 0000-0003-4950-4130 (Pakhomova)