Schematic of local Ca2+ cycling in ventricular cardiac myocytes: sarcolemmal, SR, and mitochondrial Ca2+ cycling. This schematic is a conceptual representation of the location of structures involved in the local interplay of IMFM, SR, and sarcolemmal Ca2+ cycling. ADP, adenosine diphosphate; ANT, adenine nucleotide translocase; ATP, adenosine trisphosphate; junctional sarcoplasmic reticulum, MCU, electrogenic mitochondrial Ca2+ uniporter; mNCX, Na+/Ca2+ exchanger; NHE, Na+/H+ exchanger; nSR, network SR; PTP, permeability transition pore; RaM, rapid mode of Ca2+ uptake; TT, Transverse tubule; VDAC, voltage-dependent anion channel.