Ephus

Slice electrophysiology experiments using N2AZ and scN2AZ were completed blind to the identity of the peptide. Experiments in ZnT3 KO and WT animals were completed blind to the genotype. Electrophysiology recordings in cortical cultures and DCN slices were obtained using Ephus software run in MATLAB 2012a (MathWorks). Cell parameters and response peaks were calculated using custom MATLAB scripts. For neuronal culture electrophysiology, ZX1 potentiation was measured as the percent increase in NMDAR amplitude 5 min after the application of ZX1. In slice experiments, ZX1 potentiation was calculated as the average percent increase over baseline of NMDAR or AMPAR EPSCs 10 to 15 min after the addition of ZX1 (Figs. 3, 4, 5, and 6, D to F) or 15 to 20 min after the addition of ZX1 (Fig. 6, A to C). Unpaired t tests and ANOVAs were used to compare between treatments and genotypes. To determine whether ZX1 significantly potentiated responses, paired t tests were used to compare amplitude of peak responses before and after addition of ZX1. Statistical analysis was completed in Prism 8 (GraphPad).

Whole-cell recordings are performed with a patch clamp amplifier (Multiclamp 700B; Axon Instruments) using pipettes with input resistance of 4–9 MΩ. Data acquisition is performed by National Instruments AD boards and custom software (Ephus; Suter et al., 2010 (link)). Ephus is written in MATLAB (Mathworks) and adapted to our setup. Voltages were corrected for an estimated junction potential of 10 mV. Electrodes are filled with (in mM) 115 cesium methanesulfonate (CsCH₃SO₃), 5 NaF, 10 EGTA, 10 HEPES, 15 CsCl, 3.5 MgATP, and 3 QX-314 (pH 7.25; 300 mOsm). Biocytin or Neurobiotin (0.5%) is added to the electrode solution as needed. Series resistances were typically 20–25 MΩ.