Fig. 3.

Ca²⁺ responses in chromaffin cells exposed to a single 5 ns, 17 MV/m pulse. (A) Representative traces of Ca²⁺ spikes (n = 22) in chromaffin cells exposed to a single 5 ns pulse in the absence of extracellular Ca²⁺. The arrow indicates when the pulse was delivered to the cells. (B) Averaged responses ± s.e. (n = 12) in control cells that were not subjected to the pulse displaying no Ca²⁺ activity in the absence of external Ca²⁺.