The Beneficial Effects of Electro-acupuncture at PC6 (Neiguan-point) of Gene and Protein Expressions of Classical Inward-rectifier Potassium Channels in Myocardial Ischemic Rats

Abstract

This study is aim to investigate the effect of electro-acupuncture at PC6 (Neiguan-point) on the gene and protein expressions of classical inward-rectifier potassium channels (Kir) in myocardial ischemia (MI) rats induced by isoproterenol (ISO). With ten for each one, 50 rats were divided into 5 groups which were control group, MI group, PC6 group, LU7 (Lieque-point) group and non-acupoint group. The control group was injected normal saline solution (85mg/kg), the other groups were injected ISO (85mg/kg). All the rats were injected once daily for two days and recorded electrocardiograms (ECGs) after every injection. Electro-acupuncture (EA) was operated at PC6, LU7 and non-acupoint respectively in the rats of PC6 group, LU7 group and non-acupoint group after twice injections. EA was performed to these three groups with disperse-dense wave (4-20Hz), pulse amplitude of 14V, 20mins a day remaining 7 days. The gene and protein expressions of Kir2.1, Kir2.2 and Kir2.3 were analyzed by Western Immunoblotting Technology (Western Blot) and Real-time Fluorescence Quantitative Polymerase Chain Reaction (RT-PCR). But it is regrettable that we did not detect meaningful gene and protein expressions Kir2.3, and the expressions of Kir2.1 and Kir2.2 in MI induced groups were lower [The gene and protein decreased 39.4±27.3% and 38.7±17.1% respectively.] than control group (P<0.05). Compared with MI group, the results of PC6 group and LU7 group increased [PC6 group: the gene and protein increased 42.9± 25.0% and 42.2±10.0% respectively. LU7 group: the gene and protein increased 23.8±50.1% and 21.1±32.5% respectively.] obviously (P<0.05) after EA, furthermore the expressions of PC6 group were higher [The gene and protein increased 15.4±16.7% and 17.3±60% respectively.] than LU7 group (P<0.05). The results show that PC6 has a better positive effect than LU7 on MI rats, and the mechanism is probably that EA at PC6 can significantly increase the gene and protein expressions of Kir2.1 and Kir2.2.