Sea0400

OHP was purchased from Sigma Chemical Co. (Milan, Italy). It was dissolved in physiological solution to make a stock solution of 1 mg/mL, which was diluted with medium to obtain the working concentration of 7.5 µM. This concentration has been selected in a similar range to the mean plasma concentrations in patients treated with OHP [64 (link),70 (link)] and able to induce a relevant reduction in neurite elongation after exposure. The strong and selective NCX inhibitor SEA0400 [58 (link)] was purchased from Sigma Chemical Co. (Milan, Italy). It was dissolved in dimethyl sulfoxide (DMSO) to make a stock solution of 1 mM, which was diluted with medium to obtain the 20 µM concentration; this concentration was selected after proof-of-concept experiments testing a scaling dose of SEA0400 (1, 10, 20, and 30 µM) and selecting the most promising dosage in terms of neuroprotection. The inhibition effect of SEA0400 was evaluated by a 3 h pre-treatment of SEA0400 then followed by the OHP exposure. Pre-treatment was mandatory on the basis of our previously published data, demonstrating that neuroprotection against OIPN is obtained modulating ion channels/currents before OHP exposure [25 (link)].

Angiotensin II (Peptide Institute, Osaka, Japan), losartan (Wako Pure Chemical Industries, Osaka, Japan), PD123,319 (Sigma-Aldrich, St. Louis, MO, USA), angiotensin I (Peptide Institute, Osaka, Japan), captopril (Sigma-Aldrich, St. Louis, MO, USA), chymostatin (Sigma-Aldrich, St. Louis, MO, USA) and nickel(II) chloride hexahydrate (Sigma-Aldrich, St. Louis, MO, USA) were dissolved in water. Carvedilol (Tokyo Chemical Industry, Tokyo, Japan), xestospongin C (Wako Pure Chemical Industries, Osaka, Japan), SEA0400 (synthesized in our faculty according to the reported method [75 (link)]), 2-APB (Sigma-Aldrich, St. Louis, MO, USA) and ryanodine (Wako Pure Chemical Industries, Osaka, Japan) were dissolved in dimethyl sulfoxide (DMSO). They were added to the organ bath to obtain the desired final concentration.

BTX and TTX were from Latoxan (Valence, France). VTD was from Santa Cruz Biotechnology (Dallas, TX, USA), Tf2 and pompilitoxin (β-PMTX) were purchased from Smartox Biotechnology (Saint Egrève, France) and PbTx-2 was a gift from Andrea Bourdelais (University of North Carolina Wilmington, Wilmington, NC, USA). BIII 890 CL, such as BI 55 CL, was kindly provided by Boehringer Ingelheim (Biberach an der Riss, Germany) and Bay K8644 was from Alomone (Jerusalem, Israel). All other reagents and solvents, including Fura-2 AM, Pluronic^®-F127 acid, ICA-121431, SN-6, SEA-0400, deltamethrin, thapsigargin, nifedipine, and cadmium chloride (CdCl₂), were obtained from Sigma-Aldrich Merck (Saint-Louis, MO, USA) or Thermo Fisher Scientific (Waltham, MA, USA).