[Effect of electroacupuncture at "Neiguan" (PC 6) on cardiac function and inflammatory factors of acupoint area in rats with acute myocardial ischemia].

ABSTRACT

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Neiguan" (PC 6) on cardiac function and cardiomyocyte apoptosis in rats with acute myocardial ischemia (AMI), and to explore the correlation between myocardial protective effect of EA and inflammatory factors i.e. interleukin-1ß (IL-1ß) and interleukin-17 (IL-17) of "Neiguan" (PC 6) area. METHODS: A total of 40 male SD rats with normal ultrasonic cardiogram were randomized into a sham-operation group, a sham-operation plus EA group, a model group and an EA group, 10 rats in each group. The AMI model was established by ligating the left anterior descending (LAD) branch of the coronary artery in the model group and the EA group, while the threading without ligating was adopted in the sham-operation group and the sham-operation plus EA group. In the sham-operation plus EA group and the EA group, EA at bilateral "Neiguan" (PC 6) was applied, with disperse-dense wave, 2 Hz/100 Hz in frequency and 2 mA in density, once a day, 20 min a time for 3 days. The cardiac ejection fraction (EF) and fractional shortening (FS) were measured by ultrasonic cardiogram to evaluate the cardiac function, the cardiomyocyte apoptosis was detected by TUNEL staining, the infiltration of inflammatory factors of "Neiguan" (PC 6) area was observed by H.E. staining, the expression of inflammatory factors IL-1ß and IL-17 of "Neiguan" (PC 6) area was detected by immunofluorescence staining. RESULTS: Compared with the sham-operation group, EF and FS were decreased (P<0.001), the average optical density of cardiomyocyte apoptosis was increased (P<0.001), the infiltration of inflammatory factors was obvious in skin dermis of "Neiguan" (PC 6) area in the model group; the positive expression of IL-1ß and IL-17 of "Neiguan" (PC 6) area was increased in the model group and the sham-operation plus EA group (P<0.001, P<0.01). Compared with the model group, EF and FS were increased (P<0.01), the average optical density of cardiomyocyte apoptosis was decreased (P<0.01), the infiltration of inflammatory factors was aggravating in skin dermis of "Neiguan" (PC 6) area, and the positive expression of IL-1ß and IL-17 of "Neiguan" (PC 6) area was increased in the EA group (P<0.001, P<0.01). CONCLUSION: Electroacupuncture at "Neiguan" (PC 6) can improve the cardiac function and reduce the apoptosis of cardiomyocyte in rats with acute myocardial ischemia, its mechanism may be related to the regulation of the inflammatory factors of "Neiguan" (PC 6) area.