Figure 6. Rapamycin protects against AMA-induced mitochondrial depolarization and respiration dysfunction in HL-1 cardiomyocytes. (A) Cells were pretreated with vehicle control or 1 µM rapamycin for 16 h, followed by treatment with 50 µM AMA for an additional 24 h, in the absence or presence of rapamycin. Cells were subsequently trypsinized, resuspended in Claycomb media and routine respiration analyzed. Data are derived from three independent experiments. *p < 0.05; **p < 0.01. (B) Cells were pretreated with vehicle control or 1 µM rapamycin for 16 h, followed by incubation with 50 µM AMA for an additional 24 h, in the absence or presence of rapamycin. Cells were subsequently stained with 50 nM TMRM and imaged using epifluorescence microscope. Representative images are shown. Arrows represent cells with no Δψ_m. Arrowheads represent swollen mitochondria. Rapa; rapamycin.