Inhibitor 1 of Protein Phosphatase 1 Regulates Ca²⁺/Calmodulin-Dependent Protein Kinase II to Alleviate Oxidative Stress in Hypoxia-Reoxygenation Injury of Cardiomyocytes

Figure 12

Effects of I1PP1 knockdown on CaMKIIδ alternative splicing disorder, cell injury, and oxidative stress in cardiomyocytes after H/R injury. (a) After I1PP1 siRNA or NC siRNA was transfected into neonatal rat cardiomyocytes, expressions of I1PP1 in the cardiomyocytes were quantified by western blot. GAPDH was used as a loading control. (b) After I1PP1 siRNA or NC siRNA was transfected into neonatal rat cardiomyocytes, cells were subjected to hypoxia for 4 h followed by 12 h reoxygenation. The mRNA levels of CaMKIIδA, CaMKIIδB, and CaMKIIδC of the cardiomyocytes after reoxygenation were detected by quantitative real-time PCR. 18S was serviced as a housekeeping mRNA. (c) LDH release in the culture medium was measured. (d) ATP level of the cardiomyocytes was measured. (e) Mitochondrial ROS was measured using MitoSOX. Mitochondrial localization of the MitoSOX signal was confirmed by colocalization with MitoTracker Green and quantified using ImageJ analysis software. . Plots represent the ; . Statistical significance: compared with NC; ^# and ^## compared with NC+H/R.

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