The Relative Relationship Of Stimulation Effects On Rat Brachycardia Between Different Stimulus Intensities Of Electro-acupuncture And Drug Dose Intensity

1.Objective To observe the Difference of the Regulating Effect on Rat Brachycardia Between different maintain doses of propranolol (Inderal) and different stimulus intensities of electro-acupuncture (EA) at "Ximen" point, to study the differences of the effects between different doses of drug and different stimulus intensities of EA, to provide clues for the quantitative evaluation of the acupuncture effect and to provide the scientific basis for clinical operations.2.Methods Brachycardia was induced by propranolol in SD rats. Using different maintaining dosage of propranolol and different stimulus intensity (2mA,4mA,6mA) of EA at the left side "Ximen" point to investigate the different regulating effects on heart rate(HR), mean arterial pressure (MAP), left ventricular systolic pressure (LVSP) and other indicators and the amount of efficiency..3.Results The HR, cardiac function (LVSP,+dp/dtmax, t-dp/dtmax),MAP were observed, There were significant differences of HR, MAP and LVSP between different maintaining dosages of propranolol (P﹤0.05); In comparison with the model group,different stimulus intensities of EA at Ximen point all had an improving effect on HR and LVSP (P﹤0.01), the effect size of the trend is6mA>4mA>2mA, and there was no significant difference on the impact of MAP(P﹥0.05);2mA,4mA,6mA Ximen group compared with the model of high-dose group, the differences of the indicators are extremely significant significance (P﹤0.01);HR and cardiac function of group4mA and6mA was significantly different when compared with2mA.(P﹤0.05)but has no significant differences between each other.(P﹥0.05). Different stimulus intensities of EA has no significant difference on MAP (P>0.05).2mA Ximen group compared with the model of low-dose group, the indicators of the study has no significant differences (P﹥0.05). In comparison with the model of low-dose group,4mA,6mA Ximen group both has significant differences on heart rate,LVSP and+dp/dtmax (P﹤0.05) and has no significant differences on t-dp/dtmax,MAP.There was significantly difference of effect of group4mA combind with high-dosage when compared with2mA,4mA,6mA Ximen group(P﹤0.05), There was no significant difference of effect of group4mA combind with low-dosage when compared with4mA and6mA Ximen group (P﹥0.05). There were significant differences of HR, LVSP and+dp/dtmax between group4mA combind with low-dosage and2mA Ximen group(P<0.05);but has no significant difference on t-dp/dtmax,MAP (P﹥0.05).4.Conclusion(1) The drug dose-effect relationship:the effects of differences in different concentrations to maintain the administration on heart rate, cardiac function, MAP and other indicators, its effect in descending order: the model of high-dosage group> The model group> model of low-dosage group, rather than the drug concentration.(2) EA dose-effect relationship:the strength of EA to stimulate the effect size differences, a strong stimulus can get a better effect, the effects of descending order of:6mA Ximen group>4mA Ximen group>2mA Ximen group. The difference between the6mA Ximen group and4mA Ximen group effect wasn’t statistically significant, indicating that when the electro-acupuncture stimulation intensity reaches a certain amount of its effect increases slowed down.(3) The effect of differences between an EA to stimulate and the amount of drugs to stimulate the amount of effect is considerable:2mA Ximen group and the model of low-dosage group,6mA Ximen group and4mA Ximen low-dosage group had no statistical significance, this have shown that the effects of2mA the effects of electrical stimulation and drug concentration difference between the two groups to a certain extent quite.(4) There are differences in the dose-effect relationship between acupuncture and drug: the effect of the difference between the2mA the Ximen group and4mA the Ximen high-dose group has a very significant statistical significance, does not have the equivalence between the two, indicating that high concentrations of maintain the administration can make the heart function of rats to reduce, and beyond the electro-acupuncture can regulate the physiological range, which prompted the effects of acupuncture to effectively play must be based on the body within the adjustable range of physiological and pathological stimulation.