Guangxitoxin 1e

All drug solutions were applied to the HEK293 cells using a fast perfusion system (ALA scientific Instruments, Farmingdale, NY, USA). Control recordings were obtained with fast perfusion of ECS solution. Retigabine (Alomone Labs, Jerusalem, Israel) was dissolved in DMSO to obtain a stock solution of 100 mM. The working concentrations (0.1–300 μM) were obtained by diluting the stock solution in ECS solution. Guangxitoxin–1E (Alomone Labs) and TTX (Sigma-Aldrich, Schnelldorf, Germany) were dissolved and diluted in ECS solution to obtain the stock (100 μM and 5 mM) and working (100 nM and 5 μM) solutions.

The dissecting aCSF contained (in mM): 25 NaCl, 188 sucrose, 1.9 KCl, 1.2 NaH₂PO₄, 10 MgSO₄, 1 CaCl₂, 26 NaHCO₃, 25 glucose and 1.5 kynurenic acid. The recovery solution contained (in mM): 119 NaCl, 1.9 KCl, 1.2 NaH₂PO₄, 10 MgSO₄, 1 CaCl₂, 26 NaHCO3, 20 glucose and 1.5 kynurenic acid. The recording aCSF contained (in mM): 127 NaCl, 3 KCl, 1.25 NaH₂PO₄, 1 MgC_l2, 2 CaCl₂, 26 NaHCO₃, 10 glucose. The intracellular solution for patch-clamp recordings contained (in mM): 140 KMeSO₄, 10 NaCl, 1 CaCl₂, 10 HEPES, 1 EGTA, 3 Mg-ATP and 0.4 GTP-Na₂ (pH 7.2–7.3, adjusted with KOH). NMDA, DA, 5-HT and methoctramine were supplied by Sigma-Aldrich; Clozapine-N-oxide (CNO) by Tocris and Hello-Bio; and guangxitoxin-1E by Alomone Labs. All drugs were dissolved in H₂O.