Synaptic transmission in autaptic excitatory munc18-1 neurons expressing M18WT or a non-phosphorylatable Munc18-1 variant, M18Y473F, was tested with whole-cell patch clamp electrophysiology.(G) PDBu was bath applied during 0.05 Hz stimulation. Maximum potentiation of EPSC amplitude (M18WT: 2.56 ± 0.48 fold, n=7; M18Y473F: 2.82 ± 0.98 fold, n=8, t-test with Welch correction, p = 0.8168). 