COL3A1 and atrial fibrillation: IHC analysis showed (Figure 6A) that the expression of TGF-β2 (Figure 6B), COL1A2 (Figure 6D), COL3A1 (Figure 6E), SMAD3 (Figure 6F), PARP1 (Figure 6I) were significantly higher in the female LSP-AF group, but not in the male LSP-AF group.