Click on image to view larger version.

Figure 5 Recording of transient inward currents in a hyperthyroid (A) and a control (B) pulmonary vein (PV) beating cardiomyocyte. The cardiomyocytes were depolarized from –40 mV to +40 mV for 3 s and then repolarized to –40 mV. The transient inward currents were indicated by upward arrows. The inset shows the various clamp protocols. The hyperthyroid and control PV cardiomyocytes had similar electrical capacitance.