Figure 5. 5-HTP significantly improves doxorubicin-induced oxidative damage in H9c2 cells. (A) Fluorescence microscopy image of intracellular calcium ions, bar = 100 μm; (B) DCFH-DA probe detects reactive oxygen species in each group of cells; (C) Intracellular MDA levels in different treatment groups; (D) LDH release in the supernatant is shown. *P < 0.05 vs. the Control group, #P < 0.05 vs. the DOX group.