A brief overview of electroporation pulse strength-duration space: a region where additional intracellular effects are expected
J. C. Weaver, K. C. Smith, A. T. Esser, R. S. Son, T. R. Gowrishankar Bioelectrochemistry 87:236-43. 2012.
Electroporation (EP) of outer cell membranes is widely used in research,
biotechnology and medicine. Now intracellular effects by organelle EP
are of growing interest, mainly due to nanosecond pulsed electric fields
(nsPEF). For perspective, here we provide an approximate overview of EP
pulse strength-duration space. This overview locates approximately some
known effects and applications in strength-duration space, and includes
a region where additional intracellular EP effects are expected. A feature
of intracellular EP is direct, electrical redistribution of endogenous
biochemicals among cellular compartments. For example, intracellular EP
may initiate a multistep process for apoptosis. In this hypothesis,
initial EP pulses release calcium from the endoplasmic reticulum,
followed by calcium redistribution within the cytoplasm. With further
EP pulses calcium penetrates mitochondrial membranes and causes changes
that trigger release of cytochrome c and other death molecules.
Apoptosis may therefore occur even in the presence of apoptotic
inhibitors, using pulses that are smaller, but longer, than nsPEF.