Octoxynol 9

The following drugs and reagents were used in this study: endothelin-1, oxaliplatin, and octoxynol-9, all obtained from Sigma-Aldrich (St. Louis, MO, USA). endothelin-1 (100 ng) was dissolved in saline and administered intradermally on the dorsum of the hind paw, in a volume of 5 μl, using a 30-gauge hypodermic needle attached to a microsyringe (10 μl; Hamilton, Reno, NV, USA) by a short length of polyethylene tubing (PE-10). oxaliplatin (dissolved in saline to a concentration of 2 mg/kg), used to induce painful peripheral neuropathy [16 (link), 28 (link), 32 (link)], and octoxynol-9 (0.5 % solution in saline, at a volume of 1 ml/kg), used to evaluate the contribution of the endothelium to nociceptive mechanisms [4 (link), 13 (link), 14 (link)], were administered intravenously via tail vein injection, followed by a bolus injection of an equal volume of saline before removal of the injection needle. Drug doses were selected based on the results of our previous studies [3 (link), 4 (link), 16 (link), 33 (link)].