Experimental study on the effect of ligustrazine in the prevention of intimal proliferation of deendothelial artery

Ligustrazine possesses multiple pharmacologicaleffects including anti- platelet,anticoagulation,calci-um antagonism and so on[1,2 ] and is able to interfer-ing with multiple cascades of restenosisafter percuta-neou transluminal coronary angioplasty ( PTCA) .Toevaluate the possibility of using ligustrazine in theprevention of restenosis,we investigated the effectsof ligustrazine on the intimal thickening ofair- injuredcarotid artery of rats,and examined the effects ofligustrazine on the prolif…     

Effect of Electroacupuncture Stimulation on mRNA Expression of Angiotensinogen,Angiotensin Ⅱ Type 1 Receptor,Endothelin-1,and Endothelin A Receptor in Spontaneously Hypertensive Rat Aorta

Objective: To observe the effect of electroacupuncture(EA) stimulation on the expressions of angiotensinogen(AGT), angiotensin Ⅱ type 1 receptor(AT1R), endothelin-1(ET1), and endothelin A receptor(ETAR) m RNA in spontaneously hypertensive rat(SHR) aorta. Methods: Eighteen male SHRs were randomly divided into three groups, an SHR group, an SHR Baihui(DU 20) and Zusanli(ST 36) acupoint(SHR-AP) group, and an SHR non-acupoint(SHR-NAP) group, with 6 rats in each group. Six Wistar rats were used as a control. Rats in the SHR-AP group were stimulated by DU 20 and ST 36 acupoints, both of which were connected with EA. EA was handled one time every Monday, Wednesday and Friday, for total 24 times(8 weeks). SHRNAP rats were acupointed at a 15°angle flat into 0.5 cm to two points, which were 1 and 2 cm from rail tip separately. EA parameters were the same as the SHR-AP rats. SHR control rats and Wistar rats were fixed without EA. Real-time quantitative polymerase chain reaction(PCR) was used to measure AGT, AT1 R, ET1, and ETAR m RNA expression in rat aorta. Results: EA stimulation significantly reduced rat aorta vascular AGT, ET1, ETAR and AT1 R m RNA expressions in the SHR-AP and SHR-NAP groups(P0.01). Among these four genes, AT1 R m RNA expression was significantly lower in the SHR-AP than in the SHR-NAP group(P0.01). Conclusion: EA could reduce the AT1 R m RNA expression in SHR-AP rat aorta, indicating a potential mechanism for the hypotensive effects of EA.     

Effect of Berberine on Expression of Hepatocyte Nuclear Factor-4α in Rats with Fructose-induced Insulin Resistance

The effects of berberine on the expression of hepatocyte nuclear factor-4α(HNF-4α) in liver of rats with fructose-induced insulin resistance and the molecular mechanism of berberine preventing insulin resistance were investigated.The experimental animals were divided into two groups of 16 animals each.The control group received a control routine diet containing 60% carbohydrate,and the study group a high-fructose diet containing 60% fructose as the sole source of carbohydrate.At the end of 6 weeks these were each subdivided into two groups.One was administered with berberine [187.5 mg/(kg·d) in 5 g/L carboxymethyl cellulose] by intragastric intubation and the other group was treated with a vehicle(5 g/L carboxymethyl cellulose).The rats were fed on the same dietary regimen for the next 4 weeks.After the experimental period of 10 weeks,plasma glucose,insulin and triglyceride levels were measured.HOMA insulin resistance index(HOMA-IR) was assayed.Immunohistochemistry,semiquantitative RT-PCR and western blot were used to detect the expression of HNF-4α in liver.Compared with control diet,fructose feeding induced hyperinsulinemia,HOMA-IR and increased triglyceride(all P<0.01).Berberine prevented the rise in plasma insulin(P<0.01),HOMA-IR(P<0.01) and triglyceride(P<0.05) in the fructose-fed rats.No change in plasma glucose was seen among these groups.The mRNA and protein expression of HNF-4α was decreased in the fructose-fed rats,but berberine could promote its expression.It was concluded that berberine could prevent fructose-induced insulin resistance in rats possibly by promoting the expression HNF-4α in liver.     

Kawasaki Disease on PDGF Expression and VSMC Proliferation

The effect of serum of patients with Kawasaki disease (KD) on expression of platelet-derived growth factor (PDGF) B chain protein in vascular endothelial cells (VEC) was studied by immunocytochemical method. Meanwhile,the effects of the endothelial cell conditioned media (ECM) on expression of PDGF receptor mRNA in vascular smooth muscle cells (VSMC) and on cell cycle of VSMC were investigated by the methods of nucleic acid hybridization and flow cytometry (FCM). The results showed that the serum of patients with KD induced the expression of PDGF-B chain protein significantly. ECM significantly promoted the expression of PDGF receptor mRNA and induced the proliferation of VSMC. These data suggest that the activation of PDGF-PDGF receptor may play a role in the pathogenesis of coronary complication of KD.     

Prevention of atherosclerotic arterial stenosis and restenosis after angioplasty with Andrographis paniculata nees and fish oil. Experimental studies of effects and mechanisms.

Restenosis rate after coronary angioplasty has been up to 30%-40%. To solve this problem, we studied the effects of Andrographis Paniculata Nees (APN) and fish oil (FO, ω3 polyunsaturated fatty acids over 70%) on atheroselerotic stenosis and restenosis after experimental angioplasty and the relevant mechanisms of APN and FO. Preliminary results showed that APN can significantly alleviate atherosclerotic iliac artery stenosis induced by both decndothelialization and high cholesterol diet (HCD) and restenosis following angioplasty in rabbits. FO showed the same but milder effects than APN did. Both APN and FO significantly inhibited blood monocytes to secrete growth factors in vivo. Ca~( ) -ATPase activity of cell membrane of atherosclerotic rabbits was significantly decreased, while APN or FO, especially the former alleviated this reduction. Refined extract of APN significantly decreased in vitro resting platelet [Ca~( )]_i and in vivo the resting and thrombin-stimulated platelet [Ca~( )]_i after oral     

Effect of Berberine on Expression of Hepatocyte Nuclear Factor-4α in Rats with Fructose-induced Insulin Resistance

The effects of berberine on the expression of hepatocyte nuclear factor-4α (HNF-4α) in liver of rats with fructose-induced insulin resistance and the molecular mechanism of berberine preventing insulin resistance were investigated. The experimental animals were divided into two groups of 16 animals each. The control group received a control routine diet containing 60% carbohydrate, and the study group a high-fructose diet containing 60% fructose as the sole source of carbohydrate. At the end of 6 weeks these were each subdivided into two groups. One was administered with berberine [187.5mg/(kg·d) in 5g/L carboxymethyl cellulosel] by intragastric intubation and the other group was treated with a vehicle (5g/L carboxymethyl cellulose). The rats were fed on the same dietary regimen for the next 4 weeks. After the experimental period of 10 weeks, plasma glucose, insulin and triglyceride levels were measured. HOMA insulin resistance index (HOMA-IR) was assayed. Immunohistochemistry, semiquantitative RT-PCR and western blot were used to detect the expression of HNF-4α in liver. Compared with control diet, fructose feeding induced hyperinsulinemia, HOMA-IR and increased triglyceride (all P<0.01). Berberine prevented the rise in plasma insulin (P<0.01), HOMA-IR (P<0.01) and triglyceride (P<0.05) in the fructose-fed rats. No change in plasma glucose was seen among these groups. The mRNA and protein expression of HNF-4α was decreased in the fructose-fed rats, but berberine could promote its expression. It was concluded that berberine could prevent fructose-induced insulin resistance in rats possibly by promoting the expression HNF-4α in liver.     

INHIBITORY EFFECT OF ANGIOTENSIN Ⅱ TYPE 1 RECEPTOR-ASSOCIATED PROTEIN ON VASCULAR SMOOTH MUSCLE CELL GROWTH AND NEOINTIMAL FORMATION

Objective To investigate the mechanism of a novel angiotensin n type 1 receptor-associated protein (ATRAP) interfering with angiotensin Ⅱ type 1 (AT1) receptor-mediated vascular smooth muscle cell (VSMC) growth and neointimal formation. Methods VSMCs isolated from thoracic aorta of adult Sprague-Dawley ( SD) rats were used in this study. ATRAP Cdna was subcloned into pcDNA3 vector and then transfected into VSMCs. DNA synthesis and extracellular signal-regulated kinase (ERK) and phospho-ERK expressions in VSMCs were assayed by measurement of 3H thymidine incorporation and Western blotting, respectively. Morphological changes were observed in the balloon injured artery with or without transfection of ATRAP Cdna using 12-week-old male SD rats. Results ATRAP overexpression in VSMCs inhibited angiotensin Ⅱ (Ang Ⅱ) -induced 3H thymidine incorporation 48 hours after Ang Ⅱ stimulation (P ＜ 0.05). In VSMC, Ang Ⅱ stimulation increased the phosphorylation of ERK, which reached the peak around 60 minutes. The activation of phospho-ERK was significantly decreased by ATRAP (P ＜ 0.05). Neointimal formation was markedly inhibited by ATRAP overexpression in injuried arteries. Conclusions The AT1 receptor-derived activation of ERK plays an essential role in Ang Ⅱ-induced VSMC growth. The growth inhibitory effects of ATRAP might be due to interfering with AT1 receptor-mediated activation of ERK in VSMC growth and neointimal formation.     

Experimental Study of Adenovirus Vector Mediated-hVEGF165 Gene on Prevention of Restenosis after Angioplasty

This study evaluated the effects of adenovirus vector mediated human vascular endotheli-al growth factor-165 (hVEGF165) gene on prevention of restenosis after angioplasty. Rabbit models of bilateral carotid artery injury were established by balloon denudation. The recombinant adenovi-ruses containing hVEGF165 cDNA was directly injected into left side of the injured carotid arteries.On day 3 and week 3 after transfection the expression of VEGF was observed by RT-PCR and im-munohistochemistry. The thrombokinesis, reendothelialization (rET) and intimal hyperplasia in ca-rotid arteries were evaluated by computerized image analysis system 3 weeks after gene transfer,The changes in the VEGF gene-treated side were compared with the control side. Our results showed that 3 days and 3 weeks after hVEGF165 gene transfer the VEGF mRNA and antigen ex-pression were detected in vivo. 3 weeks after the transfer, the carotid artery rET was markedly better in the VEGF gene-treated group compared with the control. The thrombokinesis, intima are-a/media area (I/M), maximal intimal and medial thicknesses (ITmax and MTmax) demonstrated a statistically significant decrease in arteries treated with VEGF gene as compared with the control group. It is concluded that VEGF gene transfer could be achieved by intra-arterial injection of re-combinant adenoviruses. It might accelerate the restoration of endothelial integrity, inhibit throm-bokinesis and attenuate intimal hyperplasia in the injured arteries after VEGF gene transfer. This procedure could be useful in preventing restenosis after angioplasty.     

血管活性肽在大鼠血管再狭窄形成中的作用

目的 研究血管活性肽在血管再狭窄形成中的作用。方法 在大鼠主动脉内皮球囊拉伤模型上,采用放射免疫法测定大鼠血浆及主动脉组织内皮素（ＥＴ）、降钙素基因相关肽（ＣＧＲＰ）和肾上腺髓质素（Ａdm）含量以及组织中血管紧张素Ⅱ（ＡⅡ）含量,用∧３Ｈ－ＴdＲ掺入法和组织学分析观察血管平滑肌细胞（ＶＳＭＣ）增生以及血管内膜／中膜面积比值。并在培养的ＶＳＭＣ上,采用∧３Ｈ－ＴdＲ掺入法研研究血管活性肽对细胞增生的影响。采用ＲＴ－ＰＣＲ法观察血管活性肽对自发性高血压大鼠（ＳＨＲ）和ＷＫＹ大鼠的主动脉和ＶＳＭＣ高血压相关基因－１（ＨＲＧ－１）表达的影响。结果 术后１０d ,血浆及主动脉ＥＴ达高峰,分别较对照组升高６９％和1２４％（Ｐ＜０．０１）;主动态ＡⅡ含量升高８０％（Ｐ＜０．０１）。应用ＥＴ抗血清或卡托普利可明显抑制血管损伤诱导的ＶＳＭＣ增殖和内膜增厚。血浆和主动脉ＣＧＲＰ水平在术后３d升高６４％和８９％（Ｐ＜０．０１）, 术后１０d血浆和组织Ａdm分别升高１２９％和１０２％（Ｐ＜０．０１）。在体应用ＣＧＲＰ（２５μg/kg）可显著抑制管损伤诱导的ＶＳＭＣ增殖和内膜增厚（抑制率分别为６６％和７９％,Ｐ＜０．０１）。ＥＴ和ＡⅡ抑制血管ＨＲＧ－１表达,激活丝裂素活化蛋白素酶（ＭＡＰＫ）;ＣＧＲＰ和Ａdm诱导ＨＲＧ－１表达,并抑制ＭＡＰＫ活性。结论 ＥＴ和ＡⅡ可促进损伤血管内增殖,而ＣＧＲＰ和Ａdm具有代偿性抗内膜增殖作用。ＥＴ、ＡⅡ、ＣＧＲＰ和Ａdm等血管活性肽可通过调节ＨＲＧ－１表达和ＭＡＰＫ途径以调控ＶＳＭＣ增殖,影响损伤血管狭窄的形成。     

The role of hypertension-related gene in aortic vascular smooth muscle cells from mice and rats

目的　研究高血压相关基因 (HRG 1)在心血管病发病中的作用。方法　用RT PCR和Northernblot分析HRG 1的表达。用3 H TdR掺入和组织学方法检测血管平滑肌细胞 (VSMC)的增殖。结果　Northernblot分析显示 ,HRG 1mRNA不仅可在VSMC中表达 ,亦可在大鼠多种组织中表达 (心、脑、肺、肾和肝 )。此外 ,在SHR大鼠的心、脑、肾和肝组织的HRG 1基因表达均明显低于正常WKY大鼠。半定量RT PCR和组织学分析表明 ,ApoE敲除小鼠和再狭窄动物模型的HRG 1mRNA表达减少 ,并且均可见到新生内膜形成。刺激VSMC增殖的ET ,AII和IL 1可减少VSMCHRG 1mRNA的表达。ANF ,CGRP和Adm可抑制VSMC增殖 ,增加HRG 1mRNA表达。这些作用能被相应的阻断剂或抗体所阻断或抑制。结论　HRG 1是一种与VSMC增殖相关的基因 ,它在动脉粥样硬化 ,再狭窄和高血压等心血管疾病中可能具有重要作用。     

血管活性肽对同型半胱氨酸刺激平滑肌细胞增殖的实验研究

目的 观察对兔主动脉平滑肌细胞（ＶＳＭＣ）增殖起负调节作用的Ｃ－型利钠利尿肽（ＣＮＰ）、肾上腺髓质素（Ａｄｍ）、降钙素基因相关肽（ＣＧＲＰ）、生长抑素（ＳＳＴ）和甲状旁腺素相关蛋白（ＰＴＨｒＰ）等活性肽对同型半胱氨酸（Ｈｃｙ）刺激的ＶＳＭＣ增殖的影响。方法 ６只大耳白兔胸主动脉贴块法离体培养平滑肌细胞;分对照及Ｈｃｙ加不同处理因素组;＾３Ｈ－ＴｄＲ掺入测定ＶＳＭＣ增殖;差速离心分离细胞膜、胞浆及胞     

HSV-tk基因对实验性血管成形术后再狭窄的抑制作用

为探讨转染单纯疱疹病毒胸苷激酶（ＨＳＶ ｔｋ）基因联合ｇａｎｃｉｃｌｏｖｉｒ（ＧＣＶ）治疗方案用于治疗冠状动脉成形术后再狭窄的可行性,构建了携带ＨＳＶ ｔｋ基因的复制缺陷型逆转录病毒,利用该病毒将ＨＳＶ ｔｋ基因转染至体外培养的血管平滑肌细胞（ＶＳＭＣ）和大鼠腹主动脉再狭窄模型的损伤动脉中,并均给予ＧＣＶ,分别观察上述处理对ＶＳＭＣ的增殖和新生内膜的形成是否有抑制作用。结果：该方案使培养的ＶＳＭＣ增殖受抑制,抑制程度对ＧＣＶ有剂量依赖关系;既往在恶性肿瘤中发现的旁观者效应,在培养的ＶＳＭＣ中也存在。同时,该方案使大鼠腹主动脉再狭窄模型的新生内膜面积减少。但单纯转染ＨＳＶ ｔｋ基因或单纯应用ＧＣＶ无论在体外还是在体内均无上述抑制作用。提示本基因治疗方案对人类冠脉成形术后再狭窄有治疗价值。     

降钙素基因相关肽对尾加压素Ⅱ诱导的血管平滑肌增殖的影响

目的 :观察降钙素基因相关肽 (CGRP)对尾加压素Ⅱ (UrotensionⅡ ,UⅡ )刺激的血管平滑肌细胞 (VSMC)增殖的影响及机制。方法 :贴块法培养大鼠胸主动脉VSMC ;3 H -胸腺嘧啶 (3 H -TdR)掺入测定VSMCDNA合成 ;γ- 3 2 P -ATP标记的同位素法测定丝裂素活化蛋白激酶 (MAPK)活性。结果 :UⅡ (10 -8mol/L)显著促进VSMC3 H -TdR掺入和激活MAPK。与对照组比较 ,分别增加 4 8%和 2 2 6 % (P <0 .0 1)。CGRP有效抑制UⅡ诱导的VSMC3 H -TdR掺入和MAPK激活。与UⅡ组比较 10 -9、10 -8、10 -7mol/LCGRP分别使VSMC3 H -TdR掺入降低 18%、2 5 %和31% (P <0 .0 1) ,使MAPK活性分别降低 2 6 %、5 0 %和 6 4 % (P <0 .0 1)。结论 :CGRP抑制UⅡ诱导的VSMC增殖 ,其机制可能与CGRP拮抗UⅡ刺激的MAPK活性有关     

球囊血管成形术后再狭窄中ET和IGF-I的改变

目的探讨内皮素(endothelin,ET)及胰岛素样生长因子-I(insulin like growth factor-I,IGF-I)在球囊损伤血管内皮后的改变及意义。方法用自制导管制造大鼠血管内皮损伤模型,观察不同时间受损血管病理改变,同时用放射免疫法测定血浆ET及IGF-I含量结果血管内皮损伤后,随着时间延长,平滑肌细胞大量增殖造成管腔狭窄,血浆ET及IGF-I升高明显,各时间点与对照组相比均有显著性差异,且两者具有较好相关性。结论ET与IGF-I相互作用促进血管平滑肌增殖,两者可能共同参与了球囊血管成形术后再狭窄的病理过程。     

川芎嗪对PDGF-BB诱导的大鼠血管平滑肌细胞增殖和骨桥蛋白mRNA表达的影响

目的:探讨川芎嗪对血小板源生长因子(PDGF BB)诱导的大鼠血管平滑肌细胞(VSMC)增殖及骨桥蛋白mRNA表达的影响。方法:大鼠胸主动脉平滑肌细胞体外培养,PDGF BB刺激VSMC ,采用MTT法和流式细胞仪测定川芎嗪对VSMC增殖的影响,逆转录聚合酶联反应(RT PCR)测定VSMC骨桥蛋白mRNA的表达水平。结果:川芎嗪可显著地抑制VSMC增殖(P <0 .0 1) ,使细胞生长停滞于G0 /G1期;PDGF BB诱导骨桥蛋白mRNA呈高表达,川芎嗪下调了这种表达。结论:川芎嗪能抑制体外的VSMC增殖,提示川芎嗪可能作为防治血管成形术后再狭窄的一种药物。     

全反式维甲酸对球囊损伤动脉后新生内膜形成及平滑肌细胞PCNA表达的影响

①目的　观察全反式维甲酸 (atRA)对球囊损伤大鼠主动脉内皮后内膜增生及血管平滑肌细胞增殖细胞核抗原 (PCNA)表达的影响 ,探讨atRA对PTCA术后再狭窄的防治作用及其机制。②方法　 5 6只大鼠随机分为假手术组、损伤组、atRA组 ,分别于术后 2、7、1 4d取实验动脉段 ,常规病理切片、苏木精 伊红染色 ,测定管腔及新生内膜面积 ,免疫组化法测定PCNA的表达水平。③结果　atRA组较损伤组 (7、1 4d时 )新生内膜横截面积明显减少 (t=3.96、- 6 .98,P <0 .0 1 ) ,内膜 /中膜横截面积比显著下降 (t=4 .2 1、- 6 .79,P <0 .0 1 ) ,在 1 4d时管腔面积明显扩大 (t=3.98,P <0 .0 1 )。PCNA于损伤后 2d在中膜见表达 ,随后表达渐少 ;损伤后 7d ,在内膜中有表达 ;1 4d可见向管腔表面聚集现象。atRA组较损伤组PCNA阳性表达指数显著下降 (t =7.2 0～ 1 5 .39,P <0 .0 1 )。④结论　atRA能抑制PCNA的过表达 ,抑制细胞周期进程 ,从而抑制内膜增生、防治再狭窄     

大鼠胸主动脉球囊成形术后血管壁丝裂素活化蛋白激酶活性的变化

目的；丝裂素活化蛋白激酶（MAPK）与大鼠胸主动脉内皮剥脱术后平滑肌细胞（SMC）增殖的关系。方法：将剥脱术后的Wistar大鼠随机分为两组（n＝6），分别于术后7天和14天时处死取材，其血管条分别做3H－TdR参入和MAPK活性测定，并与假手术组相比较。结果：剥脱术后7天和 14天与假手术组相比，3H－TdR参入分别是后者的 2.6倍和 2． 0倍（P＜0. 01），MAPK活性分别为 7.6倍和 2. 4倍（P＜0．01）。结论：大鼠胸主动脉球囊内皮剥脱术后血管SMC发生增殖，同时MAPK活性明显升高，说明MAPK与内皮损伤后的血管壁SMC增殖有关。     

氯沙坦对球囊成形术后血管内膜增生影响的实验研究

目的研究氯沙坦抗氧化应激及对球囊成形术后血管内膜增生及核因子κB活性的影响。方法采用内皮剥脱后高脂饮食（含1．5％胆固醇）喂养制作兔腹主动脉粥样硬化模型,然后对狭窄部位行球囊成形术。术后氯沙坦组给予氯沙坦10mg／（kg·d）口服,对照组只喂生理盐水,4周后取腹主动脉行组织形态学观察及用免疫组织化学方法分析核因子κB、增殖细胞核抗原、细胞间粘附分子1的表达。结果与对照组相比,氯沙坦组内膜厚度／中膜厚度比值、内膜面积／中膜面积比值均显著减少（P〈0．01）。核因子κB及其靶基因产物细胞间粘附分子1水平、细胞增值核抗原亦因氯沙坦的干预而明显减少（P〈0．01、P〈0．05、P〈0．01）。结论氯沙坦通过抑制氧化应激,减少活性氧族生成,抑制平滑肌细胞迁移、增殖和新生内膜形成,减轻再狭窄。