Objective: To investigate the effect of "Jiaji"(EX-B 2)-electroacupuncture(EA) preconditioning on the myocardium and expression of cytochrome P 450 signaling pathways of myocardial cells in myocardial ischemia-reperfusion injury(MI/RI) rats.
Methods: Sixty male Wistar rats were randomly divided into sham operation, model, Jiaji, Neiguan(PC 6), Yanglingquan(GB 34) and Quchi(LI 11) groups (n=10 in each group). MI/RI model was established by occlusion of the descen-ding anterior branch of the left coronary artery. EA preconditioning was respectively applied to EX-B 2, PC 6, GB 34 and LI 11 for 30 min, once daily for 7 days. The ECG-ST segment was detected before and after the modeling. The contents of serum creatine kinase-MB(CK-MB) and lactate dehydrogenase(LDH) were detected by ELISA and microplate method separately. The expression levels of myocardial CYP 450 related genes cyp 1 a 1, cyp 2 b 2, cyp 2 c 11, cyp 4 a 2 were detected by Real-time PCR.
Results: Thirty minutes after ligation the changes of ECG-ST segment displacement of the Jiaji group and Neiguan group were signifi-cantly lower than that of the model group(P<0.01), and the change was significantly lower in the Neiguan group than in the model group(P<0.01) 30 minutes after reperfusion. Compared with the sham operation group, the activities of serum CK-MB and LDH were significantly increased in the model group(P<0.01). Compared with the model group, the activities of serum CK-MB and LDH were significantly decreased in the Jiaji, Neiguan and Yanglingquan groups (P<0.01). Compared with the Jiaji group, the activity of serum LDH was significantly increased in the Quchi group, while the activities of serum CK-MB were significantly increased in the Quchi and Yanglingquan groups (P<0.05). Compared with the sham operation group, the expression levels of myocardial cyp 1 a 1 and cyp 2 b 2 mRNAs were significantly higher in the model group(P<0.01), while the expression of cyp 2 c 11 mRNA was lower(P<0.01). Compared with the model group, the expression levels of cyp 1 a 1 and cyp 4 a 2 mRNAs were lower in the Jiaji, Neiguan and Yanglingquan groups (P<0.01), while the expressions of cyp 2 b 2 and cyp 2 c 11 mRNAs were higher(P<0.01). Compared with the Jiaji group, the expression of cyp 1 a 1 mRNA was lower in the Neiguan group, while the expression of cyp 2 b 2 mRNA was higher(P<0.05).
Conclusions: EA preconditioning at Jiaji(EX-B 2) can reduce serum myocardial enzymes of myocardial ischemia-reperfusion rats, lower the ST segment of electrocardiogram, up-regulate myocardial CYP 450 epoxygenase cyp 2 b 2 and cyp 2 c 11 mRNAs expression, down-regulate ω-hydroxylase cyp 1 a 1 and cyp 4 a 2 mRNAs expression, thus play a role in myocardial protection.