An apparatus for studying rapid electrophysiological responses to light demonstrated on Arabidopsis leaves

Photochem Photobiol. 1995 Nov;62(5):934-9. doi: 10.1111/j.1751-1097.1995.tb09159.x.


An apparatus for making high-resolution measurements of electrophysiological changes induced by light in plant cells was constructed. Its main components were a xenon arc lamp, an electronic shutter, a liquid light-guide, a computer equipped with an analog-to-digital converter and a computer program that controlled the shutter and data acquisition. The apparatus was used to examine transient changes in membrane potential (Vm) that occur upon illumination in Arabidopsis leaves. Light-on induced a transient hyperpolarization of 4 mV after a lag time of 0.53 s. It was followed by a much larger transient depolarization that peaked 31 s after light-on. The Vm returned to near its original value after approximately 3 min. The early changes in Vm have been proposed to result from effects of photosynthetically produced ATP on the activities of H(+)-ATPases and K+ channels at the plasma membrane. The kinetics of the initial hyperpolarization were found to be reasonably consistent with such a mechanism. It is expected that the apparatus described here will be useful in future investigations of this and other electrophysiological responses to light.

Publication types

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

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Arabidopsis / physiology
  • Arabidopsis / radiation effects*
  • Electrophysiology / instrumentation*
  • Light
  • Membrane Potentials / radiation effects


  • Adenosine Triphosphate