KCNH2 and chronic obstructive pulmonary disease: 2008) and inhibit hERG potassium channels expressed in HEK-293 and CHO cells, which play a significant role in causing drug-induced QT prolongation and cardiac arrhythmias (Frolov et al. 2011). The combination of FA with CEL prevented increases in the heart rate during four weeks of treatment in the present study. FA and vitamin B12 supplementation have been shown to attenuate isoprenaline-induced myocardial infarction and tachycardia in experimental hyperhomocysteinemic rats (Hagar 2002).