Immunohistochemical analysis combined with laser scanning confocal microscopy
hiPSC-CMs were fixed in 4% paraformaldehyde, treated with Triton X-100 and blocked with 3% BSA (sigma, USA). The cells were incubated with anti-Nav1.5 (Alomone, Israel, Lot # ASC005AN4202) diluted in 1% BSA (1:100) overnight at 4℃, in darkness. The cell was washed with PBS and incubated with Peroxidase-conjugated Goat Anti-Rabbit IgG (H+L) diluted in 1% BSA (1:400) at room temperature in the dark for 1 hour. Subsequently, DAPI was added to hiPSC-CMs, covered with a glass slide, fixed around nail polish, and photographed by Olympus FV1000 (Olympus, Japan). The images were analyzed with OLYMPUS FLUOVIEW Ver.3.1b software (Olympus, Japan).