title: Nanosecond pulse electric field (nanopulse): a novel non-ligand agonist for platelet activation.
abstract: Nanosecond pulse stimulation of a variety of cells produces a wide range of physiological responses (e.g., apoptosis, stimulation of calcium (Ca2+) fluxes, changes in membrane potential). In this study, we investigated the effect of nanosecond pulses, which generate intense electric fields (nsPEFs), on human platelet aggregation, intracellular free Ca2+ ion concentration ([Ca2+]i) and platelet-derived growth factor release. When platelet rich plasma was pulsed with one 300ns pulse with an electric field of 30kV/cm, platelets aggregated and a platelet gel was produced. Platelet aggregation was observed with pulses as low as 7kV/cm with maximum effects seen with approximately 30kV/cm. The increases in intracellular Ca2+ release and Ca2+ influx were dose dependent on the electrical energy density and were maximally stimulated with approximately 30kV/cm. The increases in [Ca2+]i induced by nsPEF were similar to those seen with thapsigargin but not thrombin. We postulate that nsPEF caused Ca2+ to leak out of intracellular Ca2+ stores by a process involving the formation of nanopores in organelle membranes and also caused Ca2+ influx through plasma membrane nanopores. We conclude that nsPEFs dose-dependently cause platelets to rapidly aggregate, like other platelet agonists, and this is most likely initiated by the nsPEFs increasing [Ca2+]i, however by a different mechanism.
authors.affiliation: Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA.
authors.forename: Jue
authors.initials: J
authors.lastname: Zhang
authors.forename: Peter F
authors.initials: PF
authors.lastname: Blackmore
authors.forename: Barbara Y
authors.initials: BY
authors.lastname: Hargrave
authors.forename: Shu
authors.initials: S
authors.lastname: Xiao
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Beebe
authors.forename: Karl H
authors.initials: KH
authors.lastname: Schoenbach
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation; D004574:Electromagnetic Fields; D018274:Electroporation / Q000379:methods*; D006801:Humans; D008024:Ligands; D036103:Nanotechnology / Q000379:methods*; D015539:Platelet Activation / Q000502:physiology / Q000528:radiation effects*; D010982:Platelet-Derived Growth Factor / Q000378:metabolism / Q000528:radiation effects*; D013997:Time Factors
chemical_list: D008024:Ligands; D010982:Platelet-Derived Growth Factor; D002118:Calcium