2.3. SA Treatment and Hypertrophic Stimulation with Phenylephrine (PE)

SA (Sigma Chemical Co., St. Louis, USA) was dissolved in 0.1% dimethyl sulfoxide (DMSO; Sigma). After culturing NRVMs in serum-free medium for 24 h, the cardiomyocytes were treated with various concentrations of SA, including 50, 100, 200, 400, and 800 μM, for 24, 48, and 72 h, for the cell-viability assay. Following this, the cardiomyocytes were exposed to PE (100 μM) for another 24 h, to induce hypertrophic stimuli [39]. In addition, the cardiomyocytes were pretreated with 100, 200, and 400 μM SA for 24 h, before inducing the hypertrophic response with PE for the functional assay.