ABSTRACT
OBJECTIVE@#To observe the effects of electroacupuncture (EA) pretreatment on the cardiac ejection fraction (EF), the number of macrophages in spleen and heart, and the expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) and interleukin-1β (IL-1β) in myocardium in mice with acute myocardial ischemia, and to explore the possible mechanism of EA pretreatment on promoting myocardial protection.@*METHODS@#A total of 30 male C57BL/6J mice were randomly divided into a control group, a model group and an EA pretreatment group, 10 rats in each group. The acute myocardial ischemia model was established by ligating the left anterior descending branch of the coronary artery in the model group and EA pretreatment group, while threading but no ligating at left anterior descending branch of the coronary artery was applied in the control group. In the EA pretreatment group, mice were intervented with EA at bilateral "Neiguan" (PC 6), disperse-dense wave, frequency of 2 Hz/15 Hz, intensity of 2 mA; each EA treatment last for 20 min, once a day, and 3-day treatment was given before model establishment. The EF value was evaluated by ultrasonic cardiogram; the number of macrophages in spleen and heart was measured by flow cytometry; the expression level of NLRP3 and IL-1β in myocardium was measured by Western blot.@*RESULTS@#Compared with the control group, the EF value was decreased in the model group (<0.001), the number of macrophages in the heart and spleen was increased (<0.001), and the expression level of NLRP3 and IL-1β in the myocardium was increased (<0.001, <0.01). Compared with the model group, the EF value was increased in the EA pretreatment group (<0.01), the number of macrophages in the heart and spleen was decreased (<0.01), and the expression level of NLRP3 and IL-1β in the myocardium was decreased (<0.01, <0.05).@*CONCLUSION@#EA pretreatment could reduce the number of macrophages in spleen and heart, down-regulate the expression of NLRP3 and IL-1β in myocardial tissue in mice with acute myocardial ischemia, which could relieve the local inflammatory response and achieve the myocardial protective effect.
Subject(s)
Animals , Male , Mice , Acupuncture Points , Electroacupuncture , Heart , Physiology , Inflammation , Allergy and Immunology , Interleukin-1beta , Metabolism , Macrophages , Cell Biology , Mice, Inbred C57BL , Myocardial Ischemia , Allergy and Immunology , Therapeutics , Myocardium , NLR Family, Pyrin Domain-Containing 3 Protein , Metabolism , Random Allocation , SpleenABSTRACT
OBJECTIVE@#To observe the effects of electroacupuncture (EA) on sympathetic nerve-related substance in myocardial tissue in mice with myocardial ischemia (MI), and to explore its possible mechanism.@*METHODS@#Thirty adult male C57BL/6 mice were randomly divided into a sham operation group, a model group and an EA group, 10 mice in each one. The model of MI was established in the model group and EA group by ligating the left anterior descending branch of coronary artery. The mice in the sham operation group were not treated with ligating at left anterior descending branch of coronary artery, but the remaining procedure was similar with the model group. The mice in the EA group were treated with EA at "Neiguan" (PC 6) with 2 Hz/100 Hz of frequency and 2 mA of intensity, 20 min per treatment, once a day for totally 5 days. No EA was given for model group and sham operation group. The electrocardiogram was recorded and △ST value was calculated to evaluate the model. TTC staining was applied to evaluate the infarct size. Immunohistochemical (IHC) method was applied to evaluate the positive nerve fiber density in myocardial tissue. Western blot method was applied to test the protein expression levels of neuregulin-1 (NRG-1), tyrosine hydroxylase (TH), growth associated protein-43 (GAP-43).@*RESULTS@#The electrocardiogram (lead II) results indicated compared with the sham operation group, the S-T segments in the model group and EA group were increased obviously (both <0.01), indicating the MI model was established successfully. The TTC staining results indicated compared with sham operation group, the infarction size was significantly increased in the model group (<0.01); compared with the model group, the infarction size in the EA group was significantly reduced (<0.01). The IHC results indicated compared with the sham operation group, the positive nerve fiber density in myocardial was increased in the model group (<0.01); compared with the model group, the positive nerve fiber density in myocardial was reduced in the EA group (<0.05). The Western blot results indicated compared with the sham operation group, the expression levels of TH, NRG-1 and GAP-43 were significantly increased in the model group (<0.01); compared with the model group, the expression level of TH and GAP-43 were significantly reduced (<0.01) and that of NRG-1 was increased in the EA group (<0.05).@*CONCLUSION@#EA could increase the expression of NRG-1 and reduce the expression of TH and GAP-43 in myocardial tissues in MI mice, which could suppress sympathetic nerve hyperexcitability after infarction to achieve myocardial protection effect.