The CKD pulmonary vein (PV) cardiomyocytes of rabbits exhibit higher SR Ca2+ contents and calcium transient amplitudes, which may be due to the enhanced phosphorylation of PLB or RyR2 and SERCA2a activity.34 KN93 (1 μmol/L) eliminated these effects.34 Our study found that ventricular cardiomyocytes from CKD mice exhibited decreased SR Ca2+ contents and Ca2+ transient amplitudes than sham mice. Here, RYR2 is linked to chronic kidney disease.