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Background:Coronary artery ectasia(CAE) is defined as a localized or diffuse non-obstructive lesion of coronary arteries. Clinically, the patients were predispose to myocardial ischemia, even myocardial infarction. The current gold standard for diagnosis of CAE is coronary angiography, and the definition of CAE is the diameter of ectatic segment measuring 1.5 times more than the diameter of an adjacent healthy reference segment. CAE was classified into four distinct types:Type 1,diffuse ectasia of two or three vessels;Type 2,diffuse disease in one vessel and localized disease in other vessels; Type 3,diffuse ectasia of one vessel only; Type 4, localized or segmental ectasia in one vessel.Recently, due to the widely spread of coronary angiography,the detection of CAE was increasing. And it is reported that the patients with CAE had a similar incidence of coronary artery events when compared to patients with coronary artery disease. Therefore the clinical manifestations, therapy and pathogenesis of CAE should be focused.The previous studies revealed that nitric oxide/endothelin 1(NO/ET1)played an important role in maintenance of vascular tone, moreover, the overexpression of ET1 may led to artery atherosclerosis, and the overexpression of NO may cause the decrease of extra cell matrix and lead to abnormal dilation. Therefore there may be relationship between NO/ET1 imbalance and CAE. Besides, the pathology of CAE is the media tunia decrease, it is reported that matrix metalloproteinase9/tissue inhibitor of matrix metalloproteinase(MMP9/TIMP1)played an important role in maitainance of homestasis of extra cell matrix, if MMP9/TIMP1 were imbalance, the extra cell matrix will decrease. We propose that MMP9/TIMP1 imbalance may play a role in the pathogenesis of CAE.Both intrinsic factors and extrinsic factors play roles in the occurrence of disease. Some studies showed that some genes variation involved in the pathogenesis of some diseases.But there are limited related researches about CAE.Up to now, ACE 16 intron, angiotensin receptor type 1 A1166C gene and MMP9 C1562T polymorphism were involved in this research area. It was reported that the ACE 16 intron variation may cause changes of angiotensin level, and AT1R A1166C variation may cause the response of vascular to angiotensin,and MMP9 G1562T may cause the change of MMP9 level,therefore lead to the dysfunction of vascular tone or decrease of extra cell matrix.It is reported that CAE was related to the interplay of vascular endothelial cell function, vascular smooth muscle cell function, and inflammatory factors. NO/ET1 can reflect the endothelial cell function and MMP9 can reflect the function of vascular smooth muscle cell and inflammatory factor. And the in vitro experiments are important to vertify the results of the in vivo experiment, it is necessary for us to carry out some in vitro experiments to evaluate the results.PARTⅠ:The characters of clinical manifestation and coronary artery angiography of coronary artery ectasiaObjective:To retrospectively analyze the clinical expression of CAE and its angiographic characteristics. Methods:From January 2005 to December 2007,25 patients with CAE diagnosised by coronary angiography at our catheterisation laboratory were included.And 39 patients with CAD and 31 patients with normal coronary artery group(NCA) were included as controls.Results:In CAE group, Most patients were male (72%),only three patients was accompanied with diabetes, thirteen patients were accompanied with hypertension. All patients with CAE were admitted for chest pain, nine of them showed abnormal ST changes in ECG,and four showed elevated ST in ECG. Among the patients with CAE, ectasia was associated with slow coronary flow in 9 patients and ectasia was associated with stenosis in 4 patients.The frequency of arterial involvement, in descending order, was right coronary artery(RCA) in 76%, left anterior descending artery(LAD) in 60%, circumflex artery(CX) in 48%,and left main artery(LM) in 8%. Ectasia affected only 1 major vessel in 44%, and all 3 vessels in 36%. Compared with the patients with coronary artery atherosclerosis and patients with normal coronary artery, patients with CAE had a lower prevalence of diabetis(12%), and there were no other significant statistics of clinical demography and other coronary artery disease risk factors such as hypertension and dyslipidemia. Conclusions:CAE was prevalent in males and the prevalence of diabetes in CAE group was less frequent. Type 1 lesion was the most common lesion of CAE, and RCA was most commonly affected.PARTⅡ:The level of NO/ET1 and TIMP1/MMP9 in patients with CAE and CADObjective:To study the serum level of NO/ET1 and their relationships of coronary artery ectasia. Methods:The cases underwent coronary angiography in our hospital during last three years were randomly collected and divided into three groups, the first one included 25 patients whose angiography were CAE, the second group included 39 cases whose results were CAD, and the third were NCA which included 31 cases. Plasma ET1、MMP9 and TIMP1 were measured by ELISA method, NO production were examined by a spectrophotometric assay based on the Griess reaction. Results: Patients with CAE had significantly higher NO compared with CAD and NCA groups(138.8±85.6umol/ml,79.5±37.4 umol/ml,93.0±46.5 umol/ml, respectively, P<0.05), there were no significant different of NO among the different types of CAE (type 1,139.2±85.6 umol/ml;type 2,103.7±48.9 umol/ml;type 3,173.3±118.5 umol/ml;type 4,112.5±28.7 umol/ml, respectively),and there were also no significant different of NO among the different number of dilated coronary arteries, (one vessel involed,116.5±43.8 umol/ml;two vessels involved,116.9±31.9 umol/ml;three vessels invovled,178.3±127.8 umol/ml, respectively).There were no significant different of ET1 among the CAE group, CAD group and NCA group(1.06±0.68 fmol/ml,1.34±0.72 fmol/ml,1.09±0.80 fmol/ml, respectively).Patients with CAE had significantly higher MMP9 in comparison with CAD and NCA group(1842.6±1001.9pg/ml,1244.9±660.7pg/ml,1166.9±888.5pg/ml, respectively, P<0.05), there were no significant different of MMP9 among the different type of CAE(type 1,2172.8±1207.5pg/ml;type 2,1595.8±820.1 pg/ml; type 3,1744.6±938.2pg/ml;type 4,1435.1±731.6pg/ml, respectively).there were also no significant different of MMP9 among the different number of dilated coronary artery(one vessel involed,1760.0±856.9pg/ml;two vessels involved,1718.6±802.1pg/ml;three vessels involved,2012.3±1311.7pg/ml, respectively). There were no significant different of TIMP1 among the CAE group, CAD group and NCA group(8139.2±769.6pg/ml,8249.6±778.9 pg/ml,8306.0±904.3 pg/ml, respectively).Conclusions:NO and MMP9 may involve the pathogenesis of CAE.PARTⅢ:The studies of ACE gene、AT1R gene and MMP9 gene polymorphism of CAE and CAD.Objectives:To study the heredity character of coronary artery ectasia, to find out the relationship between coronary artery ectasia and the ACE 16 intron, AT1R A1166C and the MMP9 C1562T gene polymorphism. Methods:The cases performed coronary angiography in our hospital last three years were randomly collected and divided into three groups, the first one including 25 patients whose angiography were CAE, the second group including 39 cases whose results were CAD, and the third were NCA which including 31 cases. And we studied the variation of ACE 16 intron, AT1R A1166C and MMP9 C1562T in all research objects through observing the length of PCR products or RFLP-PCR. Results:The frequencies of ACE 16 intron DD genotype were higher in CAD, and there were significant statistic difference between CAD and CAE(the frequencies of DD genotype among CAE, CAD, and NCA were 4%,28.2%, and 16.1%,respectively);there were no significant statistic difference of the frequencies of AC+CC genotype of ATIR and CT+TT genotype of MMP9 distribution among the three group(the frequencies of AC+CC genotype of AT1R among CAE, CAD, and NCA were 20%,5.1%,9.7%, respectively; and the frequencies of CT+TT genotype of MMP9 distribution among CAE, CAD, and NCA were 8%,17.8%,29.0%, respectively).There were no significant statistic difference of the frequencies of DD genotype of ACE 16 intron and AC+CC genotype of AT1R and CT+TT genotype of MMP9 distribution among the different types of CAE and the different number of vessels of CAE. There were no relationship between the serum level of MMP9 and MMP9 C1562T gene polymorphism.Conclusion:the DD genotype of ACE 16 intron may play a role in the pathogenesis of CAD.The variation of ACE 16 gene, AT1R A1166C gene and MMP9 C1562T gene polymorphism may not involve in the pathogenesis of CAE.PART IV:The studies of vascular endothelial cell function,vascular smooth muscle cell function and macrophage cell function in vitro.Objectives:1、To study the effects of glucose and insulin on the endothelial cell function and the effects of angiotensin on the endothelial cell function in vitro.2、To study the effects of angiotensin on the production of MMP9 of vascular smooth muscle cell and THP1 cell.3、To study the effects of MMP9 on the production of NO of vascular endothelial cell.Methods:1、Endothelial cell were cultured and stimulated by glucose and insulin and angiotensin respectively. ET1 in the medium were measured by ELISA. NO in the medium were measured by Griess reagent, and the eNOS/ETl mRNA expression were measured by RT-PCR.2、Smooth muscle cell and THP1 cell were cultured respectively,and were stimulated by angiotensin respectively. MMP9 in the medium were measured by ELISA, and TIMP1/MMP9 mRNA expression were measured by RT-PCR.3、human ubEndothelial cell were measured and stimulated by MMP9.NO in the medium were measured by Griess reagent, and the eNOS mRNA were measured by RT-PCR. Results:1、High glucose decreased the level of NO and NO/ET1 and it also elevated the level of ET1.It decreased the expression of eNOS mRNA and increased the expression of ET1 mRNA. The longer time(24h),the stronger effection. Physical dose of insulin(1.74×10-10mol/L)had no effect on the expression on NO、ET1 and NO/ET1,but high dose of insulin decreased the levels of NO and the levels of NO/ET1,increased the levels of ET1.In the presence of high glucose, physical dose of insulin protected the impairment of high dose of glucose. It elevated the levels of NO which were decreased by glucose, and decreased the levels of ET1 which were elevated by glucose. In short time(30min), high insulin protected the impairment caused by high glucose, but they decreased the level of NO and increased the level of ET1 in longer time.2、The effects of AngⅡon endothelial cell acted in dose-depedent manner, the lower level of NO,and the higher level of ET1.The effects of AngⅡenhanced with the time, the longer time, the lower level of NO,and the higher level of ET1; telmisartan、PD98059 and SB203580 blocked this effect, but PD123319 and Staurosporine did not block this effect.3、The effects of AngⅡon smooth muscle cell and THP1 cell acted in dose-dependent manner, the higher dose,the higher level of MMP9. The effects of AngⅡenhanced with time, the longer time, higher level of MMP9;telmisartan,PD98059 and SB203580 blocked this effect, but PD123319 and Staurosporine did not block this effect.4、MMP9 increased the expression of eNOS mRNA and the level of NO; and the effects enhanced with time; PD98059 and Staurosporine blocked this effect. Conclusions:1、In short time, high insulin can protect the impairment caused by high glucose, but they would decrease the level of NO and increase the level of ET1 cooperately as time went on.2、AngⅡcan decrease the level of NO and increase the level of ET1,this effect were partly through AT1R and MAPK signal cell pathway.3、AngⅡcan increase the level of MMP9, this effect were partly through AT1R and MAPK cell signal pathway.4、MMP9 can stimulate the secretion of NO in a range of dose, this effect may be partly through Erk1/2 MAPK cell signal pathway or PKC cell signal pathway.
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