PSPN and atrial fibrillation: The percentage of PSPN-immunopositive cells in the AF in the advanced degenerated stage (35.1 ± 3.6%) was significantly higher than that in the AF in the early degenerated stage (18.2 ± 5.4%, p < 0.01, Figure 9a), and the percentage of 1+ cells of PSPN in the AF in the advanced degenerated stage (24.0 ± 2.6%) was significantly higher than that in the AF in the early degenerated stage (14.3 ± 4.1% p < 0.01, Figure 9b).