Targeted patch clamping with ion conductance microscopy
Oct 9, 2012
Targeted patch clamping (TPC) combines patch clamping with ion conductance microscopy (ICM) to guide the pipette to a specific patch-clamping position. Patch clamping is vital to the study of excitable cells such as neurons, cardiomyocites and muscle fibre in electrophysiology because the technique allows the researcher to examine single or multiple ion channels in those cells. But patch clamping cannot be applied to small cells or sub-micron-size structures on the cell surface, due to the resolution limit of the incorporated optical microscope, which is used to maneuvre the patch clamp’s pipette near the cell surface. Because ICM can identify the cell surface at the sub-micron scale using the same patch-clamping pipette, TPC overcomes the optical-resolution hurdle, and greatly improves the applicability of the patch clamp and its accuracy beyond the classical technique. In this paper, live rat ventricular cardiomyocyte cells were examined with targeted patch clamping using a Park ICM. Ion-channel signals were successfully recorded at a chosen Z groove location on the ventricular cardiomyocyte.