TGFB1 and atrial fibrillation: RT‐qPCR evidenced that mRNA of TGF‐β1, collagen I, and collagen II were markedly increased in atrial tissues from the SHR‐AF group rats compared to that in those from the SHR group, whereas these mRNA were notably decreased in atrial tissues from the SHR‐AF(+sh‐FMOD) group compared to that in those from the SHR‐AF(+sh‐NC) group (Figure 7A).