Figure 3. Presynaptic loss of Rac1 increases calcium-independent neurotransmitter release.

(A) Representative recordings of mEPSCs for Rac1^+/+ (left, black) and Rac1^−/− (right, orange). (B1–B4) Rac1 deletion increased mEPSC frequency but did not affect mEPSC amplitude, rise time, or full width at half-maximal amplitude (FWHM). (C) The increased mEPSC rates at Rac1^−/− were independent of presynaptic voltage-gated calcium channels (VGCC), as blocking VGCC with cadmium (Cd²⁺) did not affect mEPSC frequency. All data shown in the figure and the detailed results of statistical tests are part of the supplementary file.