title: Probing whole cell currents in high-frequency electrical fields: identification of thermal effects.
abstract: An open-end coaxial probe is combined with a planar patch-clamp system to apply electric fields with GHz frequencies during conventional patch-clamp measurements. The combination of pulsed microwave irradiation and lock-in detection allows for the separation of fast and slow effects and hence facilitates the identification of thermal effects. The setup and the influence of radiation on the patch-clamp current are thoroughly characterized. For the independent optical verification of heating effects, a temperature microscopy technique is applied with high spatial, temporal and temperature resolution. It is shown that the effect of radiation at GHz frequencies on whole cell currents is predominantly thermal in nature in the case of RBL cells with an endogenous K(ir) 2.1 channel.
authors.affiliation: Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Geschwister-Scholl-Platz 1, 80539 Munich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Olapinski
authors.forename: Stephan
authors.initials: S
authors.lastname: Manus
authors.forename: Niels
authors.initials: N
authors.lastname: Fertig
authors.forename: Friedrich C
authors.initials: FC
authors.lastname: Simmel
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D004560:Electricity; D007473:Ion Channels / Q000502:physiology*; D008856:Microscopy, Fluorescence; D018408:Patch-Clamp Techniques / Q000379:methods*; D051381:Rats
chemical_list: D007473:Ion Channels