Effect of pertussis toxin and apelin-13 on BK_Ca channels in rat middle cerebral arterial VSM cells.

<p>Whole-cell BK_Ca currents were recorded in rat middle cerebral arterial VSM cells as described in the Methods. <b>A</b>-<b>D</b>: representative tracings depicting the currents recorded from a single VSM cell under the following sequential treatment conditions: Control (A), followed by superfusion with apelin-13 (0.1 µM, 5 min) (B), washout of apelin-13, superfusion with Pertussis toxin (PT, 100 nM, 5 min) (C), and superfusion with apelin-13 plus Pertussis toxin (D). <b>E</b>: Average whole-cell current-voltage plots of BK_Ca current. <b>F</b>: Bar graphs summarizing the average current density (pA/pF) at +50 mV obtained at each treatment condition described above. Values are mean±SEM (n=6). *<i>P</i><0.05 indicates a significant difference from the corresponding control value.