Components of the mitochondrial permeability transition pore (mPTP) according to the published literature. (a) Historical mPTP model that contains voltage-dependent anion channels (VDAC), adenine nucleotide translocators (ANT), and cyclophilin D (CypD). (b) Components of more recent models of mPTP formation. Abbreviations: IMM, inner mitochondrial membrane; OMM, outer mitochondrial membrane; PiC, phosphate carrier.