The effect of eight weeks of interval training on gene expression of Ryanodine receptor's (RyR2) calcium channels and calcium pump SERCA2a in ischemic rats

This study aimed to investigate the effect of eight weeks of interval training on gene expression of Ryanodine receptor's calcium channels and calcium pump in ischemic rats.
28 Wistar male rats (200-250 g) were used in this study. They were randomly divided into 4 groups: Sham, Ischemia, Exercise, and Exercise-ischemia. Myocardial infarction (MI) was done by closing the descending coronary artery (LAD) for 30 minutes. Exercise program on treadmill was for 8 weeks, 3 days a week for 40 minutes. The rats were anesthetized and the heart tissue was isolated 48 hours after the last training session and injections. SERCA2a and RyR2 gene expression was measured for heart tissue cells.
The results showed that SERCA2a gene expression level was increased in both groups of exercise and exercise-ischemia (p= 0.001) and this increase was significantly higher in exercise-ischemia group (p = 0.001). Also, the results showed that 8 weeks of interval training significantly increased RyR2 gene expression level in two groups of exercise- ischemia and exercise. But a significant decrease was observed in RyR2 gene expression level in ischemia group.
Discussion and This study results show that a regular interval training program eliminates abnormal contractions associated with cardiomyopathy due to myocardial ischemia and rehabilitates cardiac muscle calcium control and increases mainly the contraction strength by the increase of left ventricle mass.