In this study, addition of CoCl2 to stretched mouse AF cells effectively inhibited the activity of the NF‐κB signaling pathway, manifested as decreased p65 expression and increased IKB expression, suggesting HIF‐1α is an important target that mediates ANG‐2 regulation of the NF‐κB signaling pathway. The gene discussed is NFKB1; the disease is atrial fibrillation.