Genetic Mouse Models in Pain Research

Male C57BL/6NCr mice were purchased from Japan SLC, Inc (Shizuoka, Japan). The Trpa1^−/− mice (stock number 006401), Trpv1^−/− mice (stock number 003770), Trpa1^flox mice (stock number 008649), Omp-Cre mice (stock number 006668), RCL-GCamP6f mice (stock number 028865), and RCL-ChR2(H134R)/EYFP mice (stock number 024109) were purchased from The Jackson Laboratory (Bar Harbor, ME, USA). Trpa1-Cre⁺ mice were generated by inserting improved-Cre^{54 (link)} at the start codon of the endogenous Trpa1 locus using CRISPR/Cas9-mediated genome editing in the ES cells^{55 (link)}. RCL-ChR2(H134R)/EYFP mice were crossed with Trpa1-Cre⁺ mice to visualize Trpa1-Cre⁺ cells. The ΔD mice were generated by crossing OMACS-Cre and Eno2-STOP-DTA mice, as reported previously^{6 (link)}. Advillin-Cre mice were kindly provided by Dr. Wang^{31 (link)}. Mice were housed under a standard 12-h light/dark cycle at room temperature of 23 ± 2 °C with humidity of 30–70% and allowed ad libitum access to food and water. Mice were at least 9 weeks old at the start of testing. The experimental protocols were approved by the Animal Research Committee of Kansai Medical University.