2 chloroethyl ethyl sulfide cees

2-chloroethyl ethyl sulfide (CEES), a monofunctional analog of sulfur mustard gas (SM; 2, 2′-dichloro diethyl sulfide) was purchased from Sigma-Aldrich Inc., MO, USA. C56BL/6 mice (male, 8-weeks old) were purchased from Charles River Laboratories, Wilmington, MA. Trpa1−/− mice were a gift from David Julius (University of California, San Francisco). The Trpa1-knock out allele was backcrossed into the C57BL/6NCrl background (>99.5%) by marker-assisted accelerated backcrossing (Charles River Laboratories). Mice were given at least 48 hr acclimation period before initiating studies. Mice were given access to mouse chow and water ad libitum. All animal protocols were approved by the IACUCs of Yale University, New Haven, CT and Duke University, Durham, NC. The TRPA1 antagonist, HC-030031, was a gift from Hydra Biosciences, Cambridge, MA; The TRPA1 antagonist, A-967079 was custom-synthesized by Medchem101 (Conshohocken, PA). Methylcellulose was purchased from Fluka (Buchs, Switzerland, Methocell MC, medium viscosity, 1200–1800 mPa.s.). MK-8825, a rodent CGRP receptor inhibitor, was a gift from Merck & Co., Inc.