LabHeart V.4.9.5 was used to model NCX activity following OGD/REOX. It is assumed that NCX is an electrogenic mechanism that transports Na+ and Ca2+ with a stoichiometry of 3:1. The LabHeart simulation generated values of the NCX current for different voltages using known and assumed values for intracellular and extracellular values of Na+, Ca2+. Values for Na+, Ca2+ affinities, voltage saturation and the position of the energy barrier were set at the default values for the simulator. These current-voltage values were then used to create I-V curves for NCX under varying ionic conditions. The reversal potential for each ionic condition was the voltage when NCX current equaled zero. [Ca2+]i was set at 100, 777 or 431 nM for the normoxic control (Con) NHE1+/+, NHE1+/+ OGD/REOX or NHE1+/+ OGD/REOX + HOE 642, respectively.