Different Membrane Pathways Mediate Ca²⁺ Influx in Adrenal Chromaffin Cells Exposed to 150–400 ns Electric Pulses

Figure 7

Peak Ca²⁺ responses in cells exposed to a 150 ns pulse at different -field amplitudes when VGCCs were blocked. Results are plotted as the averaged cell responses ± SE for cells exposed to a 3.1 and 8.7 kV/cm pulse in absence and presence of (a) 20 μM nitrendipine and (b) a cocktail of VGCCs containing 20 μM nitrendipine ( 15–25). Cells were pretreated with nitrendipine or the VGCC cocktail for 1 hr at room temperature. , significantly different from the corresponding control. , significantly different from the 3.1 kV/cm treatment group.

(a)

(b)