The Protective Effect Of Nicardipine On The Vein

Objective: Coronary artery bypass grafting is one of the most effective way to treat coronary heart disease(CHD),At present the main source of venous vascular bridge is the great saphenous vein,but it’s Severely limit to clinical application as for the ten years of patency rate is only 50%.How to protect the Vein in vitro is an important link in CABG,and is also an important aspects influencing on short and long term patency rate,If we can choose an ideal preservation solution which has the advantage of good vasodilatation, small endothelial damage,lower postoperative stenosis rate in clinical work,we Will greatly enhance the short and long term patency rate of bridge vascular and promote the further development of by pass surgery.Nicardipine is The second hydrogen pyridine class Ca2 + channel blockers,which Belongs to the second generation of calcium antagonist medicine,it can rise the levels of cell cAMP by inhibiting calcium inside and suppressing camp-phosphodiesterase,in this way,the blood vessels can obviously expanded,Especially for cerebral vascular and coronary arteries.moreover, Nicardipine has a stable property and exact curative effect.This experiment studies aim to finding Nicardipine’s protection effects on rabbit vein and providing the theoretical basis for clinical as a preservation solution in coronary-artery bypass grafting.Methods:1 30 rabbits were randomly divided into three groups, each group of 10,The blank group:Heparin and normal saline. The control group:Heparin,Papaverine and normal saline.The experimental group:Heparin,Nicardipine and normal saline.first,taking 4-5 centimeter of the external carotid vein of rabit,put it in the corresponding protection fluid for 30 minutes.Then,dividing it into A, B two paragraph.A is used for electron microscope and early light microscope examination, B is used to anastomosiswith common carotid artery.Using the ELISA method to measure the levels of each TXA2. After the completion of anastomosis,rabits should be fed continue, one month later,intercept the middle of bridge blood vessels to make the forward light microscope examination.The research results and data analyzed with SPSS13.0 software.2.The obtained data analysis was performed with the statistical software SPSS13.0.The data of each group would be tested by normality test and F test.If the data is accord with normal distribution and homogeneity of variance,we will analyze the difference of the means of the two groups and the statistical significance by independent samples t tests.If the data is accord with normal distribution but not with the homogeneity of variance,then the degree of freedom will be revised.If the data does not fit the normal distribution,the nonparametric tests will be usable. The statistical significant standard was set at p < 0.05 in our tests.Results:1 The short-term research indicators:Through light microscope we can find that the endothelial cell coverage in the blank group scored 1.775±0.321,the control group scored 1.750±0.353,and the experimental group scored2.150±0.428.Three groups’ datas were normality tested first,All of them were lined with normal distribution,Then each two of them were tested about independent sample t-test,what about the results: there was no statistically significant difference between control group and the blank group(P > 0.05),The difference between experimental group and control group was statistically significant(P < 0.05),as same as the result beween experimental group and the blank group(P < 0.05).Through the light microscope detection the short-term results were: The endothelial cell coverage of Nicardip group was obviously higher than the other two groups, and the difference was statistically significant(P < 0.05),and there was no statistically significant difference between Papaverine and heparin group.Through the electron microscopy,we found that a small amount of endothelial cells falling down in part of the experimental group,and it’s hardly to see edema or cavitation aboutendothelial cells whose form were most completed,moreover,the organelles were rare exceptions,and the continuously basement membrane was connected tightly with the surrounding cells. Control group has more endothelial cells falling down,and some of the endothelial cells became edema and cavitation,the form were basic integrity, the basement membrane has poor connection with the surrounding cells. Blank group had so catastrophic damage with the form of endothelial cells that none of complete cells can be found,as same as the basement membrane.The TXA2 level of Elisa test results: The experimental group was 48.434±12.161,The control group was60.207±10.346,The blank group was 60.457±12.272. Three groups’ datas were normality tested first,All of them were lined with normal distribution,Then each two of them were tested about independent sample t-test.The results were:there was no statistically significant difference between control group and the blank group, The difference between experimental group and control group was statistically significant,as same as the experimental group and the blank group.Results showed that the Nicardip group has lower TXA2 level than others,and there was statistically significant(P < 0.05).when it comes to the other two group,there was no statistically significant.2 The long-term research indicators: The coverage scores of vascular endothelial cell under Light microscopy are: blank group 1.550±0.197,control group 1.600±0.316,experimental group 1.975±0.321. Three groups’ datas were normality tested first,All of them were lined with normal distribution,Then each two of them were tested about independent sample t-test.The results were:there was no statistically significant difference between control group and the blank group,but the difference between experimental group and control group was statistically significant,as same as the experimental group and blank group.It’s showed that under light microscope the Nicardip group had better vascular endothelial cell coverage than others in a long-term detection.Conclusion:1 Nicardipine had a better effect than papaverine in protecting the venous endothelial cells in rabbit vein, Mainly in the protection of endothelial cells’ integrity and coverage.2 The Nicardipine group generated lower TXA2 level than Papaverine group.