2.1 Animals
All experiments were approved by Animal Care and Use Committee of the Nanfang Hospital, Southern Medical University and adhered to National Institute of Health Guide for the care and use of laboratory animals. In the first part of the study, male wild-type (WT) C57BL/6J mice (8-12 weeks, 25-30 g) were purchased from the Experimental Animal Center of Southern Medical University. In the second part, maleTrpm4−/− mice on C57BL/6J background (8-12 weeks, 25-30 g, Shanghai Model Organisms China) and WT littermates were bred from homozygous mating. All mice were housed in the specific pathogen-free facility with a 12 h light/dark cycle and offered free access to water and stand chow. The genotype of mice was confirmed by extracting DNA from mice tail and then separating DNA in agarose gel. All efforts were made to minimize the number of animals used in this study and their suffering.