Frequency-dependent interaction of ultrashort E-fields with nociceptor membranes and proteins

Bioelectromagnetics. 2011 Feb;32(2):148-63. doi: 10.1002/bem.20620. Epub 2010 Oct 28.


We examined the influence of ultrashort pulses (USP) on sensory neurons. Single and high frequency bursts of 12 ns E-fields were presented to rat skin nociceptors that expressed distinct combinations of voltage-sensitive proteins. A single E-field pulse produced action potentials in all nociceptor subtypes at a critical threshold (E(c) ) of 403 V/cm. When configured into high frequency bursts, USP charge integrated to reduce the action potential threshold in a frequency and burst duration-dependent manner with E(c) as low as 16 V/cm (4000 Hz, 25 ms burst). There was no evidence of electroporation at field intensities near the E(c) for nociceptor activation. USP bursts activated a late, persistent Ca(++) flux that was identified as a dantrolene-sensitive Ca(++) -induced Ca(++) release (CICR). Influx of Ca(++) into the cell was required for the CICR and resulted in a reduction of the single pulse E(c) by about 50%.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Calcium / metabolism
  • Cell Membrane / metabolism*
  • Electricity / adverse effects*
  • Electroporation
  • Male
  • Nociceptors / cytology*
  • Nociceptors / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Sodium Channels / metabolism*
  • Time Factors


  • Sodium Channels
  • Calcium