Protein and RNA expression of acid-sensing ion channels 2 and 3 in myocardial ischemia rats induced by isoproterenol.

Objective: To investigate the impact of electro-acupuncture at the Neiguan (PC 6) acupoint on protein and RNA expression of acid-sensing ion channel 2 (ASIC2) and ASIC3 in myocardial ischemia rats.

Methods: Fifty male Sprague-Dawley rats were used, weighing (230 ± 50) g. The rats were randomized into a normal group A, model group B, Neiguan (PC 6) group C, Lieque (LU 7) group D, and A-shi points group E. There were 10 rats in each group. Rats were continuously administered 85 mg/ kg intravenous isoproterenol daily to establish the model. Successfully modeled rats in groups C, D, and E were given electro-acupuncture treatment. Each group of rats was sacrificed with chloral hydrate (1 mL/100 g) intraperitoneal injection. The left ventricular myocardium was extracted and placed at -70 °C until use. Western blot analysis and real-time PCR were performed to assay protein and RNA expressions of ASIC2 and ASIC3, respectively. Fold changes in RNA expression were quantified with the 2^ (-ΔΔCt) method. Blood samples were drawn from the aorta abdominalis and tested for creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) levels using enzyme-linked immunosorbent assay.

Results: Myocardial ischemia rats given electro-acupuncture at the Neiguan (PC 6) acupoint had significantly lower protein and RNA expression of ASIC2 and ASIC3, and CK-MB and LDH levels, compared with model rats (P < 0.01).

Conclusion: Electro-acupuncture at the Neiguan (PC 6) acupoint can not only decrease the protein and RNA expression of ASIC2 and ASIC3, but also inhibit the opening of ASICs and reduce the cardiomyocyte damage in myocardial ischemia rats.