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

Figure 6

Effect of VGCC blockers on the Ca²⁺ response of the cells to a 150 ns pulse. Results are plotted as the averaged cell responses ± SE for cells exposed to a 3.1 kV/cm pulse in the absence and presence of (a) 100 nM ω-agatoxin IVA, (), (b) 20 nM ω-conotoxin GVIA, ( 8–14) (c), 5 μM nitrendipine, ( 9–12), and (d) a cocktail of all three blockers, ( 11–13). The arrow indicates when the pulse was delivered to the cells. Cell were pretreated with the blockers for 1 hr at room temperature. , significantly different from control.

(a)

(b)

(c)

(d)