Fig. 1.

α-SNAP increased the rate of quantal release of catecholamine at ∼170 nm[Ca²⁺]_i. A, Simultaneous recording of [Ca²⁺]_i and amperometric events from a control cell. The cell was voltage clamped at −80 mV, and [Ca²⁺]_i was buffered to ∼170 nm by diffusion of Ca²⁺-buffer solution via the whole-cell pipette. B, [Ca²⁺]_i and amperometric events from a cell recorded with 60 nm α-SNAP in the pipette solution. In B, the frequency of amperometric events obviously increased after ∼6 min of whole-cell dialysis.