The maximum stimulus-evoked exocytosis in the presence of stx3pep is indicative of the RRP and the RP. (A) The total ΔCm1 evoked by the four stimulus trains exceeded 100 fF for terminals under standard control conditions or in the presence of the control peptide, stx3con. By contrast, total ΔCm1 was reduced in the presence of stx3pep (p < 0.02) and ATP-γS (p ≤ 0.05) relative to their respective controls, stx3con, and standard control. Dotted line denotes 50 fF. (B) The cumulative total capacitance increase evoked by the stimulus trains, total ΔCmtotal exceeded 500 fF under standard control conditions or in the presence of the control peptide stx3con. By contrast, total ΔCmtotal was significantly reduced in the presence of either stx3pep (p < 0.004) or ATP-γS (p < 0.002) relative to their respective controls, stx3con and standard control. Dotted line denotes 150 fF. Standard control terminals (n = 6), ATP-γS terminals (n = 6), stx3pep terminals (n = 6), and stx3con terminals (n = 5).