RYR2 and atrial fibrillation: RyR2 phosphorylation at Ser2814 and Ser2808 showed higher levels in the AF heart than in the control, suggesting increased Ca2+ release by RyR2 (Figure 4D, 2.5 ± 0.7 vs. 0.7 ± 0.1, p < 0.01, Figure 4E, 2.5 ± 0.4 vs. 0.7 ± 0.1, p < 0.01).