Detection of Mitochondrial Permeability Transition Pore Opening Level

The opening level of mitochondrial permeability transition pore (MPTP) in PAFs and PASMCs was measured using the MPTP assay kit (Genmed). First, cell medium was discarded, and preheated cleaning solution was added. Next, cells were incubated with working solution at 37°C and protected from light for 30 minutes. After washing 3 times with 0.01 mol/L PBS, fluorescent images were captured and analyzed using a laser scanning confocal microscope. As a fluorescent probe, calcein AM can be captured easily by mitochondria and presents with green fluorescence. When MPTP opens, calcein is released into cytoplasm, with fluorescent quenching.