MYBPC3 and chronic kidney disease: In contrast, the phosphorylation of cMyBP-C at the PKA-specific Ser-282 site was significantly hypophosphorylated in both CKD male and female hearts (0.28 ± 0.03 and 0.67 ± 0.03, respectively, p < 0.05, n = 12–14 independent determinations) compared to the sham-operated groups (1.00 ± 0.03 in male hearts and 1.00 ± 0.01 in female hearts, respectively, p < 0.05; Figure 7D).