TGFB1 and atrial fibrillation: In this study, we had four major findings, including 1) RD reduced the susceptibility to AF in a rabbit model of atrial fibrosis induced by AAC, 2) RD was verified to reduce atrial fibrosis and decrease RAAS activation induced by AAC, 3) RD decreased protein expression of pro-fibrotic factors as TGF-β1 and CTGF in atrial tissues, and 4) The relationship among RD, RAAS, atrial fibrosis and the susceptibility to AF was preliminary established.