The Effect of a Novel Highly Selective Inhibitor of the Sodium/Calcium Exchanger (NCX) on Cardiac Arrhythmias in <i>In Vitro</i> and <i>In Vivo</i> Experiments - Fig 9

<p><b>Panel A</b> shows representative Ca²⁺ transient tracings and cell shortenings when NCX reverse mode was facilitated by reduction of the external NaCl to 70 mM. Under this setting, the application of 1 μM ORM-10962 significantly decreased the magnitude of Ca²⁺ transient (red line) and cell shortening (red line) compared to 70 mM NaCl containing Tyrode’s solution (black lines). In this case the APD₉₀ of the action potential was slightly increased (<b>Panel B</b>). The forward mode of NCX was increased by 600 nM forskolin (<b>Panel C</b>). Under this setting 1 μM ORM-10962 further increased the amplitudes of the transient and cell shortening (red lines). The mid-plateau potential of the action potential significantly decreased (<b>Panel D</b>). The change of Ca²⁺ transient and cell shortening under reverse (black column) and forward mode (grey column) enhancement were depicted by bar graphs in <b>Panel E</b>.