Primary rat Schwann cells were produced as described (Poitelon & Feltri, 2018 (link)) and grown with DMEM supplemented with 4 g/L glucose, 2 mM L-glutamine, 5% bovine growth serum, 2 μM forskolin, 50 ng/ml nerve growth factor, penicillin and streptomycin. Schwann cells were not used beyond the fourth passage. Rat dorsal root ganglia (DRG) neurons from Sprague–Dawley rat embryos were isolated at embryonic day 14.5 embryos. DRG were dissociated by treatment with 0.25% trypsin and mechanical trituration and 1.5 DRGs were seeded on collagen-coated glass coverslips as described (Poitelon & Feltri, 2018 (link)). For GsMTx-4 (Alomone, STG-100) treatment, GsMTx-4 was solubilized in DMEM at 100 nM, then Schwann cells were treated with either DMEM or 100 μM of GsMTx-4 for 48 h (Bae et al., 2011 (link)). For Yoda-1 (Tocris, 5586) treatment, Yoda-1 was solubilized in DMSO at 1 mM, then Schwann cells were treated with either 0.5% of DMSO or 5 μM of Yoda-1 for up to 1 h (Lacroix et al., 2018 ).