Capsaicin-induced Mouse Pain Model

All experiments were approved by the Ethics Committee of West China Hospital of Stomatology (Chengdu, China). All experiments were performed in accordance with relevant guidelines and regulations and executed in compliance with the ARRIVE guidelines (https://arriveguidelines.org). Briefly, 8–10-week-old, male, C57BL/6 mice (20–25 g) were provided by Dossy Experimental Animals Company (Chengdu, China). The animals were exposed to a 12-h light-and-dark cycle. Mice were allowed for a standard diet with free access to food and water. The mice were randomly allocated into the following four groups: control group that consisted of 31 mice (n = 31) receiving phosphate-buffered saline injection; capsaicin group that consisted of 31 mice (n = 31) receiving capsaicin injection; capsazepine group that consisted of 31 mice (n = 31) receiving capsazepine injection; capsazepine + CGRP group that consisted of 28 mice (n = 28) receiving capsazepine and CGRP overexpression lentivirus injection.