| ObjectivesCardiovascular disease is the highest human fatality rate of one of the three major diseases,with a serious threat to human health.A great deal of clinical researches and empirical studies show that there is unique curative effect on this myocardial ischemia treated by acupuncture on Neiguan(PC6) point.In this study,we produced acute myocardial ischemia in rabbits by ligating anterior descending branch of the left coronary artery.Then the rabbits were treated with electro-acupuncture(EA) at Neiguan point,after when we detected the contents of norepinephrine(NE) and dopamine(DA) and 5-hydroxytryptamine(5-HT) in blood plasm,so as to explore the mechanisms of EA at Neiguan point on myocardial ischemia from the point of view of monoamine neurotransmitter.Methods40 clean Japanese big-ear rabbits(weighing 1.8-2.5 kilograms ) were randomized into 4 groups as Normal Group(n=10 ),Sham Operated Group (n=10 ),Model Group(n=10 ),Electro-acupuncture(EA ) Group(n=10 ). We applied Simpson's method to produce acute myocardial ischemia in rabbits by ligating anterior descending branch of the left coronary artery. Electrocardiogram in LeadⅡwas recorded with RM6280 Four Channel Physiological Recorder.Evidence for a successful intervention was a cyanotic left anterior ventricular wall,local wall distension,as well as elevated S-T segment of the electrocardiogram(ECG) and peaking T waves after tightening the ligature.For Sham Operated Group,thoracotomy was performed to expose the heart,the thread was clung to the coronary artery and the operation was finished with no ligations.For Model group,bilateral Neiguan points were inserted with needles for from 0.5 to 1 centimeters and then connected to G6805-ⅡElectro-Acupuncture Apparatus with the parameters:continuous wave,7 Hz,1 mA for 30 minutes.ECG and left ventricle myocytes transmembrane potential in each groups were recorded. And contents of norepinephrine(NE) and dopamine(DA) and 5-hydroxytryptamine(5-HT) in blood plasm were determined at 60 minutes after ligation.Results1.ST segments were observed no significant differences among groups before operation.Although somewhat increased immediately at and after ligation,the ST segment potential of Sham Group was of no statistical significance as compared with Normal Group(P＞0.05).Immediately and at 30 minutes,60 minutes after ligation,the Model Group showed apparent elevation in ST segment potential(P＜0.01),which demonstrated at 30 minutes obviously higher than that of Operation Group and Normal Group but notably lower than that of Model Group(P＜0.05 ),as well as at 60 minutes obviously lowered as close to normal.2.NE content in blood plasm of Model Group was obvious higher than that of Sham Operated Group and Normal Group,with an extremely significant difference statistically(P＜0.01).While the content was obviously lower in EA Group as compared with Model Group,the statistical comparison shows a significant difference(P＜0.05).which suggests that Electro-acupuncture can restraint the release of NE content in blood serum. 2.DA content in blood plasm of Model Group was obvious higher than that of Sham Operated Group and Normal Group,with an extremely significant difference statistically(P＜0.01).While the content was obviously lower in EA Group as compared with Model Group,the statistical comparison shows a significant difference(P＜0.05).which suggests that Electro-acupuncture can restraint the release of DA content in blood serum.3.5-HT content in blood plasm of Model Group was obvious higher than that of Sham Operated Group and Normal Group,with an extremely significant difference statistically(P＜0.01).While the content was obviously lower in EA Group as compared with Model Group,the statistical comparison shows a significant difference(P＜0.05).which suggests that Electro-acupuncture can restraint the release of 5-HT content in blood serum.Conclusions:1.EA at Neiguan point promotes recovery of ST segment,therefore is proved the myocardioprotective effects against myocardial ischemic injury.2.The remarkably elevation of norepinephrine(NE) and dopamine(DA) and 5-hydroxytryptamine(5-HT) in blood plasm after acute myocardial ischemia suggests a role of monoamine neurotransmitter in the process of acute myocardial ischemic injury.3.Electro-acupuncture may realize cardioprotective effect through regulating the release of NE and DA and 5-HT in blood plasm.
|
PDF Full Text Request