Effects of STA on cell surface area and protein/DNA ratio changes induced by NE. (A) Representative fluorescent micrographs of cardiomyocytes; F-actin is visualized with Alexa Fluor 488-conjugated phalloidin stain (green), whereas the nucleus is visualized by DAPI staining (blue), ×400. (B) Quantification of cell surface area, n = 150. (C) Ratio of Protein/DNA, n = 5. (D) Cell viability, n = 4. The data are expressed as the mean ± SEM. *P < 0.05 versus control, #P < 0.05 versus NE. NE: norepinephrine, CAR: carvedilol, STA: stachydrine.