Fig. 1

Simultaneous extracellular and intracellular recordings. a Examples of extracellular (Ext) recordings in which transmitter release produces a corresponding postsynaptic response detected by the intracellular (Int) electrode. b Example traces with missing events. An extracellular trace is shown where there is a signal detected (Ext), but with the absence of an intracellular (Int) response (no mEJP) in the intracellular trace. Arrows indicate the presence of an extracellular event, but a missing intracellular event. c Muscle 4 of MHC::mCD8-GFP-Sh larvae under transmitted light microscope showing extracellular (single arrowhead) and intracellular microelectrode (double arrowhead) placement. d Same NMJ showing the fluorescence of CD8-Sh-GFP and how boutons were selected. e Cartoon representation of muscle, bouton and electrode placement