Effect of metabolic syndrome on the response to arterial injury

Background

Metabolic syndrome is now an epidemic in the United States population. Intimal hyperplasia remains the principal lesion in the development of restenosis after vessel wall injury. The aim of this study is to characterize the changes induced in wall morphology in the developing intimal hyperplasia within a murine model in the presence of diabetes (type 1) and metabolic syndrome.

Methods

Control (wild type B6), Non Obese Diabetic, and metabolic syndrome (RCS-10) mice were used. The murine femoral wire injury model was used in which a micro wire is passed through a branch of the femoral and used to denude the common femoral and iliac arteries. Specimens were perfusion fixed and sections were stained with hematoxylin and eosin and Movat stains such that dimensional and compositional morphometry could be performed using an ImagePro system. Additional stains for proliferation and apoptosis were used.

Results

In control mice, the injured femoral arteries develop intimal hyperplasia, which is maximal at 28 d and remains stable to day 56. Sham-operated vessels do not produce such a response. In diabetic mice, the intimal response increased 5-fold with a 2-fold increase in proteoglycan deposition, whereas in the metabolic syndrome mice there was a 6-fold increase in the intimal response and a similar increase in proteoglycan deposition. Collagen deposition was different with a 22-fold increase over control in collagen deposition in diabetes and a 100-fold increase over control in collagen deposition in metabolic syndrome as compared with the control injury mice. Maximal vascular smooth muscle cell (VSMC) proliferation was decreased in both diabetes and metabolic syndrome compared with controls, whereas early cell apoptosis in both diabetes and metabolic syndrome was sustained over a longer period of time compared with wild-type mice.

Conclusions

These data demonstrate that development of intimal hyperplasia is markedly different in diabetes and metabolic syndrome compared with controls, with an increase in collagen deposition, a reduction in VSMC proliferation, and an increase in early VSMC apoptosis. These findings suggest that preventative strategies against restenosis must be tailored for the diabetic and metabolic syndrome patients.     

鼠双微体-2基因在醛固酮增多症大鼠模型主动脉平滑肌中的表达

目的 观察醛固酮对大鼠主动脉平滑肌鼠双微体-2基因(MDM2)表达的影响.方法 将SD大鼠随机分为3组,每组8只.采用皮下给药的方法建立醛固酮增多症模型,其中醛固酮组经微量渗透泵持续释放醛崮酮(1μg/h);醛同酮+螺内酯组除给予等量醛固酮外,每日行螺内酯灌胃(每日100mg/kg);对照组仅泵空白溶剂.尾套法检测大鼠血压,4周后处死所有大鼠,测定血钾、钠、醛固酮浓度及血浆肾素活性.分别采用逆转录.聚合酶链反应(RT-PCR)、Westerill blot、免疫组织化学检测主动脉平滑肌MDM2基因表达.结果 (1)成功建立醛同酮增多症大鼠模型:醛固酮组2周后血压明显升高,血钾下降,呈现低肾素、高醛固酮特征,与对照组比较差异有统计学意义(P<0.01);(2)醛固酮组主动脉平滑肌MDM2基因表达明显高于对照组(P<0.01).螺内酯可抑制醛固酮的上述作用(P<0.01).结论 醛固酮可促进血管平滑肌细胞中MDM2的表达,而螺内酯可拮抗其效应.     

趋化素样因子1对大鼠血管平滑肌细胞增殖活性的影响

目的探讨大鼠趋化素样因子（Cklfl）在体外对血管平滑肌细胞增殖活性的影响。方法将pCDB／Cklfl真核表达载体（实验组）和空载体pCDB（对照组）分别转染COS-7细胞，获取上清液，刺激原代培养的大鼠主动脉血管平滑肌细胞，以噻唑蓝（MTT）法检测细胞增殖情况。并比较在光镜和电镜下形态学的改变。结果以10％胎牛血清稀释的实验组上清与对照组相比，MTT法检测的A值在刺激大鼠平滑肌细胞48和72h后差异有统计学意义（P〈0．05和P〈0．01，n=5）。两组细胞光镜下形态学无明显差异，电镜下经Cklfl刺激后的平滑肌细胞亚细胞器及肌丝和致密体增多。结论Cklfl在血管平滑肌的增殖过程中发挥重要作用。     

靶向RNA干扰骨桥蛋白基因的慢病毒载体对血管平滑肌细胞增殖凋亡的影响

目的 构建大鼠骨桥蛋白(OPN)基因的shRNA慢病毒表达载体,并观察其对大鼠血管平滑肌细胞(VSMC)增殖和凋亡的影响.方法 针对OPN基因的不同部位设计3对shRNA的寡核苷酸片段,克隆到慢病毒载体PLKO.1中,构建靶向OPN基因的慢病毒载体PLKO.1-OPN-shRNA,检测并筛选最佳抑制效率的shRNA干扰载体.并将其转染大鼠血管平滑肌细胞,用逆转录-聚合酶链反应(RT-PCR)检测VSMCs OPN mRNA表达水平;蛋白免疫印迹法(Western blot)检测VSMC OPN蛋白表达水平;噻唑蓝(MTT)比色法和流式细胞仪检测沉默OPN基因后对VSMC增殖和凋亡能力的影响.结果 靶向OPN慢病毒表达载体构建成功.重组慢病毒载体PLKO.1-OPN-shRNA转染后可显著抑制VSMCs的OPN mRNA及蛋白的表达水平,OPN蛋白表达明显下降,其中以PLKO.1-OPN2-shRNA最为明显,达到90％以上;转染PLKO.1-OPN2-shRNA后72 h的细胞增殖能力[吸光度(A)值=0.365 ±0.011]明显低于未处理组(A值=0.941±0.028)和阴性对照组细胞(A值=0.941±0.040,P＜0.05);而早期细胞凋亡率(20.44±2.69)％和晚期细胞凋亡率(16.79±1.01)％均明显高于未转染组和阴性对照组(P＜0.01).结论 成功构建并筛选最佳抑制效率的靶向OPN慢病毒表达载体PLKO.1-OPN2-shRNA,该载体能有效抑制大鼠血管平滑肌细胞增殖,并促进细胞凋亡.     

Vascular effects of poly-N-acetylglucosamine in isolated rat aortic rings.

BAACKGROUND: Poly-N-acetylglucosamine (p-GlcNAc) is a secretion of marine diatoms that is known to be useful in controlling bleeding. As a component of promoting hemostasis, p-GlcNAc is thought to exert vasoconstrictor effects in arteries. The present study was undertaken to determine whether p-GlcNAc induced a significant vasoconstrictor effect and, if so, what the mechanism of this effect might be. MATERIALS AND METHODS: We examined vascular effects of p-GlcNAc on isolated aortic rings obtained from Sprague-Dawley rats. The rings were suspended in organ baths and precontracted with U46619, a thromboxane A2 mimetic. RESULTS: p-GlcNAc produced a concentration-dependent vasoconstriction over the range of 14 to 100 microg/ml. At a concentration of 100 microg/ml, p-GlcNAc significantly contracted aortic rings by 133 +/- 20 mg of developed force (P < 0.01). Neither a deacetylated derivative of p-GlcNAc nor a structurally related macromolecule, chitin, contracted rat aortic rings, indicating a specificity for p-GlcNAc. The vasoconstriction to p-GlcNAc was totally abolished in deendothelialized rat aortic rings, suggesting that an endothelial component is essential to the vasoconstriction. Pretreatment with the endothelin ET(A) receptor antagonist, JKC-301 (0.5 and 1 microM), significantly diminished p-GlcNAc-induced vasoconstriction by 57 to 61% (P < 0.01). However, p-GlcNAc did not significantly diminish nitric oxide release from rat aortic endothelium. CONCLUSION: These results provide evidence that p-GlcNAc significantly contracts isolated rat aortic rings via an endothelium-dependent mechanism, partly via enhancement of endothelin-1 release from endothelial cells.     

Remifentanil produces vasorelaxation in isolated rat thoracic aorta strips

BACKGROUND: Remifentanil can cause transient instability in hemodynamic variables. However this change may not be solely the result of autonomic or central nervous system inhibition or of centrally mediated vagal stimulation. In this study, the aim was to examine the direct effects of remifentanil on isolated thoracic aorta strips in vitro. METHODS: Forty-five Wistar rat thoracic aorta rings were isolated, and contraction-relaxation responses were recorded. RESULTS: In aortic rings precontracted with phenylephrine or potassium chloride, remifentanil produced concentration-dependent relaxation in both endothelium-intact and denuded rings (P<0.001). Remifentanil induced significantly greater relaxation in intact rings than in those denuded of endothelium, regardless of whether they were precontracted with phenylephrine hydrochloride or KCl (P<0.001). When the endothelium was present, remifentanil produced greater relaxation in KCl-contracted rings than in PE-contracted rings at lower concentrations (10-9 and 10-8), and similar relaxation at higher concentrations (10-7 and 10-6). However, when the endothelium was removed, relaxation was similar in both solutions, at all concentrations (10-9 to 10-6). In intact rings, pretreatment with L-NO-ARG or indomethacin reduced the degree of remifentanil-induced relaxation. In Ca+ +/- free media, calcium-dependent KCl contractions were inhibited in a dose-dependent manner by remifentanil (P<0.001). CONCLUSION: Remifentanil vasodilates by an endothelium-dependent mechanism, involving prostacyclin and nitric oxide released from the endothelium. Its endothelium-independent vasodilation probably occurs via the suppression of voltage-sensitive Ca++ channels.     

伊马替尼抑制大鼠静脉移植物内膜增生

目的 观察伊马替尼对自体移植静脉内膜增生的影响.方法 建立大鼠自体颈外静脉移植模型,实验分为4组:移植组、低剂量给药组、高剂量给药组及对照组.移植4周后取移植静脉,行病理学检查观察内膜增生情况,免疫组织化学及Western blot法检测PDGFRβ、ERK及P-PDGFRβ、P-ERK蛋白表达情况.结果与对照组比较,移植组和低剂量给药组内皮下平滑肌细胞大量增生,静脉内膜显著增厚,管腔明显狭窄,高剂量给药组内膜无明显增厚.Western blot结果显示,移植组血管P-PDGFRβ蛋白含量(P-PDGFRβ/GAPDH)较对照组明显增加(0.81±0.06比0.18±0.02,P<0.05),而高剂量给药组较移植组明显减少(0.32±0.03比0.81±0.06,P<0.05),低剂量给药组与移植组比较差异无统计学意义(P>0.05),P-ERK蛋白表达亦呈同样趋势变化.结论 高剂量伊马替尼能有效抑制自体移植静脉内膜增生,其机制可能与抑制PDGF信号通路蛋白磷酸化,从而抑制平滑肌细胞增殖有关.     

缺氧诱导因子-1α与同源盒基因共转染在移植静脉重塑态的表达

目的 探讨缺氧诱导因子(HIF-1α)和同源盒基因(gax)共转染在移植静脉组织中的表达状态.方法 Wistar大鼠16只随机分为实验组和对照组,每组8只,均行自体静脉移植术,实验组移植静脉行缺氧诱导因子(HIF-1α)和同源盒基因(gax)共转染,对照组则未行基因转染,于术后14 d取出移植的静脉,分别采用逆转录-聚...     

Old age does not affect shortening velocity or content of contractile and cytoskeletal proteins in the rat detrusor smooth muscle

The influence of old age on mechanical properties of the urinary bladder was investigated using smooth muscle strips from urinary bladders of control (14–16 weeks) and old-age (104 weeks) female Sprague-Dawley rats. Bladder weight of the aged rats had increased by about 30%. The maximal shortening velocity and stiffness in skinned activated urinary bladder fibers from old animals were unchanged compared to controls. The relative content of intermediate filament proteins to actin and the relative content of myosin to actin was unchanged. The concentration of myosin was unchanged (about 6.5 g/mg wet weight). The results suggest that old age is not associated with pronounced changes in the cellular contractile and cytoskeletal proteins or in the mechanical properties of the contractile machinery. The age-related changes in mechanical properties previously reported for intact smooth muscle from urinary bladder are most likely due to alterations in the activation systems.     

微小RNA-17-5p下调同源盒蛋白HOXB13抑制血管平滑肌细胞增殖的研究

目的:探讨微小RNA(miR)-17-5p调控同源盒蛋白(HOXB13)的分子机制。方法:从SD大鼠胸主动脉分离和培养血管平滑肌细胞(VSMCs);利用细胞计数试剂盒检测细胞增殖;反转录定量聚合酶链反应检测miRNA和miR-17-5p的表达;细胞转染miR-17-5p mimics、anti-miR-17-5p和小干...     

硫酸吲哚酚对大鼠主动脉平滑肌细胞增生影响的机制研究

目的：探讨硫酸吲哚酚（indoxyl sulfate,IS）对大鼠血管平滑肌细胞（vascular smooth muscle cell,VSMC）增生的影响以及这种变化和氧化应激的关系。方法实验均分为8组：正常组、IS 100μM组、IS 300μM组、IS 500μM组、辛伐他汀10μM＋正常组、辛伐他汀10μM＋IS 100μM组、辛伐他汀10μM＋IS 300μM组、辛伐他汀10μM＋IS 500μM组。采用WST-1法检测VSMC增殖情况;硫代巴比妥酸法检测培养基中丙二醛（malondialdehyde,MDA）含量;ELISA方法测定晚期氧化蛋白产物（advanced oxidation protein products,AOPP）。结果与正常组比较,IS 300μM组和 IS 500μM 组上清液的 WST-1（OD 值）[（1.55±0.27）比（1.18±0.25）与（1.73±0.30）比（1.18±0.25）,P〈0.01]含量、MDA含量[（2.60±0.47）μg/ml比（1.59±0.21）μg/ml与（2.82±0.54）μg/ml比（1.59±0.21）μg/ml,P〈0.01]和 AOPP 含量[（67.94±8.58）μmol/L 比（54.97±8.46）μmol/L与（72.09±9.49）μmol/L比（54.97±8.46）μmol/L,P〈0.01]均明显增高。与同浓度 IS 组相比,辛伐他汀10μM＋IS 300μM 组和辛伐他汀10μM＋IS 500μM 组上清液 WST-1（OD 值）[（1.22±0.24）比（1.55±0.27）与（1.32±0.30）比（1.73±0.30）,P〈0.05]、MDA[（1.64±0.38）μg/mL 比（2.60±0.47）μg/ml 与（1.70±0.40）μg/ml 比（2.82±0.54）μg/ml,P〈0.01]含量和 AOPP 含量[（55.56±7.41）μmol/L比（67.94±8.58）μmol/L 与（55.54±6.80）μmol/L 比（72.09±9.49）μmol/L,P〈0.05]均明显降低。大鼠 VSMC 上清液的 WST-1含量与 MDA 含量呈正相关（r=0.621,P〈0.01）,大鼠VSMC上清液的WST-1含量与AOPP含量呈正相关（r=0.581,P〈0.01）。结论 IS可浓度依赖性地促进大鼠 VSMC增生,其作用可能与 IS增加 VSMC的氧化应激有关;辛伐他汀可抑制此作用。     

超氧化物阴离子与兔髂动脉再狭窄关系的研究

目的:研究血管壁超氧化物阴离子(O2·)与其再狭窄间的关系。方法:作兔髂动脉再狭窄模型40只,正常对照组2只。于一次损伤术后28d、二次损伤术后即刻、1、2、3、7、14、28、56、84d自术侧髂动脉取材,并与对侧髂动脉自身组织作对照;研究组共10组,每组4只。应用DHE孵育、激光共聚焦显微镜检测动脉壁之O2·表达,并对结果进行统计学分析;用免疫组化EnVision技术检测动脉壁平滑肌细胞和巨噬细胞,以定位产生O2·的细胞。结果:①血管壁O2·荧光均值测定,实验各组与正常及自身对照比较有显著性差异(P<0.01);②新生内膜O2·荧光强度与正常及自身对照比较有显著性差异(P<0.05);③内膜和外膜中释放O2·以巨噬细胞为主,中膜中以平滑肌细胞为主;④新生内膜、中膜和外膜中O2·释放互相相关。结论:血管壁O2·的产生可相互影响,平滑肌细胞和巨噬细胞参与了O2·的释放。以O2·为主的细胞内活性氧可能在再狭窄中起重要作用。     

不同浓度的咪唑安定对兔离体气管平滑肌收缩的影响

目的研究不同浓度的咪唑安定对离体气管平滑肌的舒张作用,以明确咪唑安定在10-5mol/L浓度时是否能够产生较为明显的舒张作用。方法用高浓度氯化钾、乙酰胆碱、电脉冲三种刺激因素诱发兔离体气管平滑肌收缩,并观察三种不同浓度的咪唑安定对其的影响。结果1.5×10-5mol/L的咪唑安定对三种刺激因素诱发的气管平滑肌收缩不产生明显抑制作用;1.5×10-4mol/L和3.0×10-4mol/L的咪唑安定可显著抑制上述三种刺激因素诱发的气管平滑肌收缩(P<0.05或P<0.01),普萘洛尔和中枢性苯二氮卓艹类受体阻断药氟马西尼不能拮抗咪唑安定对气管平滑肌的舒张作用。结论咪唑安定在10-5mol/L左右的浓度时对兔离体气管平滑肌收缩不能产生明显的抑制作用。     

罗比卡因对乙酰胆碱诱发兔离体气管平滑肌收缩的抑制作用

目的探讨不同浓度罗比卡因对乙酰胆碱(Ach)诱发兔离体气管平滑肌收缩的影响。方法取兔气管环,浸浴在K-H液中,气管一端固定张力换能器,每个标本先用10-4M Ach收缩,然后使其回到基线,加入3×10-4M(Ⅰ组)、5×10-4M(Ⅱ组)和10-3M(Ⅲ组)三种不同浓度的罗比卡因测定其对Ach诱发的离体气管平滑肌收缩的影响,不加罗比卡因的为对照组(C组)。结果三种浓度的罗比卡因对Ach诱发的收缩均可产生一定的抑制作用(P<0.05,P<0.01)。与C组比较,Ⅰ组10 min张力明显下降,为C组的50%(P<0.05),Ⅲ组2 min张力下降至C组的70%(P<0.01),并在10 min左右张力降到基线。Ⅲ组与Ⅰ组张力比较,3 min后有显著性差异(P<0.05),Ⅲ组与Ⅱ组张力比较,10 min后有极显著性差异(P<0.01)。结论三种浓度的罗比卡因对10-4M Ach诱发的收缩均有抑制作用,并且随着罗比卡因浓度的增加抑制作用增强。     

改良组织块法成人主动脉血管平滑肌细胞的培养

目的 建立成人主动脉血管平滑肌细胞体外培养的有效方法.方法 无菌条件下分离成人主动脉的平滑肌层,剪成1 mm3的碎片,0.1％ Ⅰ型胶原酶预处理1h,组织块贴壁法,以含胎牛血清20％的DMEM低糖培养基培养.倒置显微镜观察培养细胞的形态学特点,免疫荧光法检测平滑肌细胞肌动蛋白(α-SMA)的表达.结果 培养至4～5d组织块边缘即有少量细胞爬出,呈长梭形,胞质丰富;培养至1～2周组织块边缘细胞融合,呈典型的“峰谷”样表现.免疫荧光染色结果显示胞质内α-SMA的表达丰富,荧光强度在(++)～ (+++).结论 胶原酶预处理组织的改良组织块贴壁法培养人主动脉血管平滑肌细胞是一种可行有效的实验方法.     

A comparison of CORVITA and expanded polytetrafluoroethylene vascular grafts implanted in the abdominal aortas of dogs

The utility of CORVITA vascular grafts, composed of an inner layer of meshed polyurethane fibers and an outer layer of meshed Dacron reinforcement, for replacement of the abdominal aorta was assessed in a canine model and compared with expanded polytetrafluoroethylene (ePTFE) grafts. CORVITA or ePTFE vascular grafts were implanted and left in place for 3 or 6 months. After removal, they were inspected macroscopically and histologically. Microspectrophotometry was used to quantify smooth muscle cells (SMCs), elastin (EL), and collagen (CL) in the media of the native artery. The patency rate of the CORVITA grafts after 6 months was 100%, whereas that of the ePTFE grafts was only 50%. Moreover, stenoses were apparent in all of the ePTFE grafts, but in only 43% of the CORVITA grafts. The intimal thickness at the distal anastomosis was significantly greater at 3 months in the ePTFE grafts (P<0.01), and there were significantly more SMCs in the host arterial media at the proximal and distal anastomoses in these grafts. Thus, better long-term patency can be expected with CORVITA grafts than with ePTFE grafts. This conferred advantage is most likely attributable to the less pronounced intimal hyperplasia which results from the proliferation of SMCs in the media of the native artery.     

诱导骨髓基质细胞成血管平滑肌细胞的研究

目的 探讨体外诱导犬骨髓基质细胞(SMSC)为血管平滑肌细胞(VSMC)及其成血管的能力.方法 用含血小板源性生长因子(PDGF-BB)10ìg/L的内皮细胞培养液-2(EGM-2)诱导,无PDGF-BB的EGM-2培养液为对照,检测a-平滑肌肌动蛋白(a-SM actin)与肌钙结合蛋白(calponin)的表达并接种于聚羟基乙酸(PGA)培养4周后取材.结果 诱导组(n=5)细胞逐步呈平滑肌样转变,表达a-SM actin与calponin,流式细胞仪阳性率分别为(45.16±0.97)%、(37.54 4±1.15)%,可成血管样结构,对照组(n=5)变化不明显,阳性率(7.92±1.04)%、(6.37±0.83)%,成血管样结构能力差.结论 体外可诱导犬BMSC为VSMC并有成血管样结构的能力.     

STAT3信号通路与血管重塑中平滑肌细胞表型转化及增殖关系

目的 观察静脉桥再狭窄模型中血管平滑肌细胞(VSMC)表型转化和增殖活性的变化,探讨信号转导子和激活子3蛋白(STAT3)的表达与VSMC表型转化及增殖活性的关系.方法 建立猪静脉桥再狭窄模型,采用血管病理形态学、免疫组织化学和免疫印迹(Western blot)方法,观察术后7、14、30 d血管蓖塑及血管壁中增殖细胞核抗原(PCNA)、平滑肌ot肌动蛋白(SM-α actin)和STAT3表达变化及其相关性.结果 (1)术后7 d新牛内膜形成逐渐增厚,于术后30 d达最大;重塑指数和外弹力板围绕面积(EELA)术后7 d稍有增大,其后不断减小,术后14～30 d明显减小(P<0.05).(2)免疫组织化学和Western blot测定STAT3蛋白显示,术后7 d中膜VSMC中阳性表达明显,术后14 d中膜VSMC和内膜VSMC中阳性表达均增加达高峰;术后30 d中膜VSMC中有较少部分阳性表达,内膜VSMC中阳性表达较14 d减少.血管中膜中STAT3和PCNA的蛋白呈显著性正相关(r=0.726,P<0.05).结论 血管平滑肌细胞的表型转化和增殖活性改变对内膜增生和血管重塑起着重要作用,STAT3信号通路与血管重塑中VSMC的增殖高度相关,参与并促进了VSMC的表型转化和增殖.     

RNA干扰对兔血管平滑肌细胞bcl-2基因表达的影响

目的研究RNA干扰(RNAi)对兔血管平滑肌细胞(VSMCs)bcl-2基因表达的干扰效应。方法用脂质体法将构建的装载靶向bcl-2基因小干扰性RNA(siRNA)的表达载体(pshRNA-bcl-2质粒)转染VSMCs(基因组),以转染空载体的细胞和加DMEM的空白细胞作为对照,采用半定量RT-PCR和Westernblot法检测bcl-2基因的表达,用MTT法检测VSMCs生长情况。结果转染siRNA的表达载体可以抑制内源性bcl-2基因在转录和转译水平上的表达,基因组bcl-2的mRNA和蛋白表达较空载体组和空白对照组明显减少(P<0.01);基因组的VSMCs生长也较空载体组和空白对照组明显受到抑制(P<0.01)。结论载体介导的RNAi技术可明显抑制内源性bcl-2基因的表达和VSMCs生长。     

血小板源性生长因子-BB影响下大鼠血管平滑肌细胞增殖及其ras蛋白的表达

目的 观察血小板源性生长因子-BB(PDGF-BB)对大鼠血管平滑肌细胞(VSMC)的增殖及其ras蛋白表达的影响.方法 体外培养大鼠VSMC并传代,将第4代VSMC分4组,设空白对照组,另设3组分别加入1、2、4 μg/L PDGF-BB进行干预,采用细胞计数、免疫组织化学及免疫荧光等方法,观察干预后1、3、7 d 3个时间点的VSMC计数、增殖细胞核抗原(PCNA)表达及相应时段ras蛋白的表达,并分析两者之间的相关性.结果 (1)在7 d内各组VSMC计数均逐渐增加,其中2 μg/L和4 μg/L PDGF-BB组的计数增长较对照组快(P＜0.05),4 μg/L PDGF-BB组较1 μg/LPDGF-BB组快(P＜0.05);(2)免疫组织化学和免疫荧光检测显示,干预3 d后各组VSMC增殖细胞百分比均表现为高PDGF-BB浓度组高于低浓度组(P＜0.05),ras蛋白荧光表达强度亦呈现相同趋势(P＜0.01).PDGF-BB干预后的VSMC的PCNA表达和ras蛋白表达呈显著正相关(r=0.735,P＜0.05).结论 PDGF-BB可以刺激体外培养大鼠VSMC增殖,并可促进其ras蛋白的表达.