Intracellular Calcium Dynamics in Cardiomyocytes

Cardiomyocytes were transfected with siRNA against SERCA2a and after 48 h, approximately 2 × 10⁶ cells were infected with adenovirus. After incubation with serum-free M199 for 4 h, intracellular calcium was detected using the Fluo-8 calcium flux assay kit (Abcam, ab112129) according to the manufacturer’s instructions [68 (link)]. In brief, the cells were loaded with calcium-sensitive probe Fluo-8 in Hanks’ buffer with 20 mM Hepes (HHBS) for 30 min at 37°C [69 (link)]. The cells were washed with HHBS twice. Afterward, the cells were excited at 490 nm and Ca²⁺-bound Fluo-8 emission was recorded at 525 nm.