Experimental Investigation On Effect Of Electroacupuncture At Neiguan Point Against Acute Myocardial Ischemia On The Content Of Polypeptide Material In Rabbit

ObjectivesCardiovaseular 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 disease treated by acupuneture 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 CGRP,NPY and ANP in blood from the point of view of polypeptide neuropeptides.Methods40 clean Japanese big-ear rabbits(weighing1.8-2.5 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 is chemia in rabbits by ligating anterior descending branch of the left coronary artery. Electrocardiogram in Lead 11 was 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.ST 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-â…¡Electro-Acupuncture Apparatus with the parameters:continuous wave,7 Hz, 0.6mA for 30 minutes.ECG and leit ventricle myoeytes transmembrane potential in each groups were recorded.And contents of CGRP,NPY and ANP in blood 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.CGRP content in blood serum was obvious lower than that of Sham Operated Group and Normal Group,with an extremely significant difference statistically(P<0.01).While the CGRP content was obviously higher in EA Group as compared with Model Group,the statistical comparison shows a significant difference(P<0.05),which suggests that Electro-acupuncture Neiguan can enhance the release of CGRP,and then achieve the anti-acute myocardial ischemia injury in rats. 3.NPY content in blood 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 NPY 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 Neiguan can restraint the release of NPY,and then achieve the anti-acute myocardial ischemia injury in rats.4.ANP content in blood 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 ANP 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 Neiguan can restraint the release of ANP,and then achieve the anti-acute myocardial ischemia injury in rats.Conclusions1.EA at Neiguan point promotes recovery of ST segment,therefore is proved the myocardioprotective effects against myocardial ischemic injury.2.The remarkably elevation of CGRP,NPY and ANP in blood after acute myocardial ischemia suggests a role of polypeptide neuropeptides in the process of acute myocardial ischemic injury.3.Electro-acupuncture may realize cardioprotective effect through regulating the release of polypeptide neuropeptides in blood and myocardial tissue.