大鼠腹主动脉平滑肌细胞培养及鉴定

目的 培养、鉴定大鼠腹主动脉平滑肌细胞.方法 采用组织贴块法分离培养大鼠腹主动脉平滑肌细胞,胰蛋白酶消化传代,相差显微镜及即用型SABC免疫组化染色试剂盒进行细胞鉴定.结果 平滑肌细胞呈梭形或长梭形生长,透射电镜可见细胞的胞浆内有很多与细胞纵轴平行的肌丝和与之相连的致密体.高倍镜下可见胞质内大量棕色、与细胞长轴平行的纤...     

大鼠肺动脉平滑肌细胞原代培养及低氧对缺氧诱导因子- 1α的影响

目的获得活力稳定、高度纯化的体外培养大鼠血管平滑肌细胞,为肿瘤研究提供实验材料;并探讨低氧对抗肿瘤药物研究新靶点：缺氧诱导因子-1α（HIF-1α）的影响。方法无菌下取SD大鼠心肺组织,然后分离出肺动脉段,分离肺动脉中膜层,用组织块贴壁法培养,倒置相差显微镜观察细胞形态、普通免疫组织化学法（SP法）进行细胞鉴定。随后,将体外培养的大鼠PASMCs,设计常氧组、低氧组H2,H6,H12,H24,用Western blotting法检测HIF-1α的蛋白表达。结果用组织贴块法成功培养大鼠PASMCs,得到生长稳定、纯度高的PASMCs,且培养与纯化可以同时进行,可获得稳定传代的细胞;HIF-1α蛋白在常氧组有少量表达,在低氧条件下,其表达明显增加。结论成功建立体外大鼠肺动脉平滑肌细胞原代培养模型;低氧条件下促进其中HIF-1α的表达;这提示HIF-1α蛋白的表达可能是肿瘤细胞适应缺氧环境的重要原因。     

High glucose enhance expression of matrix metalloproteinase—2 in smooth muscle cells

目的:通过用高糖对培养的大鼠主动脉平滑肌细胞进行干预,观察其对基质金属蛋白酶-2(MMP-2)表达的影响。方法:用组织贴块法体外培养大鼠主动脉平滑肌细胞,分组后分别予以葡萄糖0,1,5g/L进行干预。分别提取细胞总RNA和总蛋白分别进行逆转录PCR(RT-PCR),Westernblotting检测,同时取出条件培养基经酶谱法(zymography)检测分泌于培养基中的MMP-2活性。结果:经mRNA,蛋白和酶活性检测,均发现在葡萄糖浓度为5g/L时,MMP-2的表达水平较对照和1g/L时明显增加。结论:高糖促进血管平滑肌细胞和内皮细胞内MMP-2表达,提示血管细胞外基质的降解在糖尿病患者动脉粥样硬化发生机制中起着一定作用。     

消化法培养大鼠脑血管平滑肌细胞

目的建立大鼠基底动脉平滑肌细胞培养的方法。方法取大鼠基底动脉,剪成约0.2mm的小段,用含胶原酶Ⅱ型(0.5g.L-1)、弹性酶(0.15g.L-1)、透明质酸酶Ⅳ-S型(0.5g.L-1)及脱氧核糖核酸酶Ⅰ型(0.1g.L-1)的消化液在37℃消化1h。而后用含20%FCS的DMEM/F12进行培养。结果原代培养3d后细胞可少量贴壁,1wk左右可传代,细胞传代成活率达97%。光镜和免疫细胞化学染色检测第4代细胞纯度为98%。结论与目前国内培养脑血管平滑肌细胞的方法相比,本方法操作简单,培养周期短,细胞纯度高。     

大鼠血管平滑肌细胞的贴块法培养

目的:探讨大鼠血管平滑肌细胞的原代培养方法与生长特性,为中药研究提供实验材料。方法:采用组织贴块法培养,倒置显微镜观察形态,电镜鉴定,台盼蓝染色活力检测。结果:倒置显微镜和电镜观察培养的血管平滑肌细胞生长状态良好,呈现平滑肌细胞特征性的“峰—谷”状结构,台盼蓝染色约有95%以上的细胞为活细胞。结论:本培养方法简单、经济,经过一定时间的操作训练,即可成功培养出平滑肌细胞。     

高血压患者动脉平滑肌细胞培养的探讨

目的对高血压患者动脉平滑肌细胞培养方法进行探讨。方法运用植块贴壁法对高血压患者动脉平滑肌细胞进行体外培养,并用倒置显微镜进行形态学观察和用免疫组化对培养细胞进行鉴定。结果运用植块贴壁法成功培养了高血压患者动脉平滑肌细胞,培养的细胞呈典型“峰谷”样生长,免疫组化S-P法检测α-平滑肌肌动蛋白单克隆抗体(α-SMActin)表达,确认为人血管平滑肌细胞(hVSMC)。经传代培养至3～5代,细胞生长特性未见异常改变。结论植块贴壁法培养的高血压患者动脉平滑肌细胞生长稳定性好,且培养与纯化能同步进行。     

家兔动脉血管平滑肌细胞培养方法的改进

目的提高家兔血管平滑肌细胞(vascular smooth mus-cle cell,VSMC)体外培养的成功率。方法以传统的主动脉平滑肌细胞培养方法中的组织块贴壁法为基础,从动物选择、培养基配制、血管取材、组织块的大小和接种间距、培养液的量及换液量、细胞传代的时机等多个重要环节进行改进;用倒置显微镜、电镜对培养细胞进行形态学观察,并用平滑肌细胞特异性α-肌动蛋白(α-actin)单克隆抗体免疫组织化学方法进行鉴定。结果台盼蓝检查传代细胞的存活率大于97%;光镜下见培养细胞平行排列呈长梭形及"峰、谷"样结构特征;免疫组织化学染色鉴定培养细胞中VSMC的纯度为97%;电镜技术观察到VSMC完整的超微结构。结论此培养方法能提高动脉平滑肌细胞原代培养的成功率,传代后血管平滑肌细胞生物学特征的稳定性好,可作为研究血管平滑肌细胞生物学行为的有效模型。     

氯沙坦抑制ROS/ERK1/2信号途径减轻AGEs诱导的大鼠脑血管平滑肌细胞增殖

目的探讨果糖制备的糖基化终末产物(AGEs)对大鼠脑基底动脉血管平滑肌细胞(BASMC)的增殖以及氯沙坦对增殖的影响和机制。方法培养大鼠脑基底动脉血管平滑肌细胞,用CCK8法测定不同浓度(1,5,10μmol/L)氯沙坦对果糖制备的AGEs(200mg/L)预处理48h诱导血管平滑肌细胞增殖的影响。用western blotting检测AGEs以及氯沙坦处理后对ERK蛋白表达影响。结果 AGEs刺激血管平滑肌细胞增殖(0.827±0.069比0.364±0.052,P<0.01)。给予氯沙坦(5,10μmol/L)后,细胞增殖明显下降(0.658±0.064和0.381±0.058比0.827±0.069,P<0.01)。AGEs还使平滑肌细胞内活性氧簇(ROS)生成增多,并显著增加ERK1/2蛋白表达,氯沙坦则明显抑制ROS和ERK1/2蛋白水平。结论果糖制备的AGEs诱导脑基底动脉血管平滑肌细胞增殖,氯沙坦可能通过阻断AT1受体而抑制ROS和ERK1/2表达,减少平滑肌细胞的异常增殖。     

大黄素增强SD大鼠脑基底动脉平滑肌细胞BKCa电流

目的 研究大黄素对SD大鼠脑基底动脉的影响.方法 应用压力型小动脉测量仪观察给予大黄素前后脑基底动脉直径的变化;应用全细胞膜片钳技术观察大黄素对离体的SD大鼠脑基底动脉平滑肌细胞电流的调节作用.结果 (1) 大黄素舒张脑基底动脉(P<0.05);(2) 大黄素呈电压依赖性增强脑基底动脉平滑肌细胞外向电流(P<0.05);(3)大黄素呈浓度依赖性增强脑基底动脉平滑肌细胞外向电流,10-7、10-6和10-5 mol·L-1 的大黄素分别增加脑基底动脉平滑肌细胞外向电流(+ 60mV)从(173±43) pA 到(226±36) pA、(266±54) pA和(303±71) pA (P<0.05);(4) 给予10-3 mol·L-1 的BKCa通道阻断剂四乙胺(tetraethyl ammonium;TEA)不仅取消了大黄素对脑基底动脉平滑肌细胞外向电流的增强作用,而且使外向电流减小到(61.2±6.5) pA,比对照组电流减小了(0.65±0.06)倍(P<0.01).结论 大黄素通过增强BKCa通道的开放促进钾离子外流从而舒张脑基底动脉血管.     

家兔主动脉平滑肌细胞原代培养的研究

目的探索高效快速的家兔血管平滑肌细胞体外原代培养技术,为分子生物学实验提供足量可靠的细胞来源。方法取家兔主动脉中层,用刀片切成约1mm3,采用不同浓度的Ⅰ型胶原酶以及不同消化时间对组织块进行预消化,然后将组织块贴在培养瓶上进行培养。结果1.5g.L-1胶原酶消化6h后组织块细胞迁出速度及组织迁出率明显提高(P<0.05),组织块贴壁后24h即可见血管平滑肌细胞从组织块周围游离出来,呈梭形或星形,d4～5即可进行传代培养,传代后d3～4即可融合成致密单层细胞,呈典型的峰谷交错状,经免疫组化SP法鉴定有α-actin的表达,进一步确认其为血管平滑肌细胞。结论经1.5g.L-1胶原酶消化6h后组织块细胞迁出速度且迁出率明显提高,从而大大缩短原代培养的时间。     

Effects of Tween 80 on volume-regulated chloride channel and cell proliferation in rat basilar artery smooth muscle cell

Objectives We have previously found that volume‐regulated chloride current (VRCC) is involved in cell cycle progression and cell proliferation. This study was to examine the effect of Tween 80, a nonionic surfactant, on VRCC and cell proliferation in rat basilar artery smooth muscle cells (BASMCs). Methods VRCC was recorded using a whole‐cell patch clamp. Cell proliferation and cell cycle were determined by CCK‐8, cell count and flow cytometry. Key findings The results showed that endothelin‐1 promotes cell cycle transition from the G0/G1 phase to the S phase and significantly increases VRCC in BASMCs. The effect of Tween 80 on VRCC is reversible and concentration dependent. However, this chemical has no effect on the calcium‐activated chloride channel. Tween 80 also concentration‐dependently inhibits BASMCs proliferation and arrests cells in the G1/S checkpoint. The antiproliferative effect is paralleled with the inhibitory effect on VRCC. Conclutision Our study demonstrates that the inhibitory effect of Tween 80 on VRCC contributes importantly to arrest of the cell cycle and prevention of cell proliferation.     

Pharmacological implications of cellular localization of alpha1-adrenoceptors in native smooth muscle cells

1. This study examines the cellular localization of alpha1-adrenoceptors and demonstrates that binding to intracellular receptive binding sites in native smooth muscle cells may influence the pharmacological profile of agonists or antagonists. The example tissue studied was rat basilar artery. 2. An alpha1-adrenoceptor antagonist and fluorescent analogue of prazosin, BODIPY-FL prazosin (QAPB) allowed visualization, with high resolution, of both plasma membrane and cytosolic binding sites on live native cells, as previously shown in cells harbouring recombinant receptors. QAPB-associated fluorescence binding was both time- and concentration-dependent in rat basilar smooth muscle cells and affinity for alpha1-adrenoceptors was calculated from specific binding curves as 1.1 nM. 3. Concentration-dependent binding of QAPB detected in smooth muscle cells dissociated from rat basilar arteries was composed of diffuse and clustered fluorescence. Visually the diffuse component of fluorescence was the more evident up to a concentration of 5 nM QAPB. Confocal visualization of an optical section through the cell showed that the clustered component was located mainly intracellularly. In rat basilar artery smooth muscle cells the intracellular binding sites were located in close proximity to the nuclear membrane. 4. 3D models of QAPB-associated fluorescence demonstrate that a high proportion of effective binding sites are intracellular, showing not only that a high proportion of receptors are located inside the cell but also that in this location they can bind ligands. This has implications for pharmacological analysis in relation to the consequences of intracellular binding per se and for differential effects upon the pharmacology of particular ligands according to whether they can enter the cell.     

A new NO donor failed to release NO and to induce relaxation in the rat basilar artery

Nitric oxide (NO)-donors are pharmacologically active substances that in vivo or in vitro release NO. Their most common side effect is headache caused by cerebral vasodilatation. We previously demonstrated that the new NO-donor Ru(terpy)(bdq)NO](3+) (Terpy), synthesized in our laboratory, induces relaxation of rat aorta. This study aimed to verify the effect of Terpy and sodium nitroprusside (SNP) in basilar artery. We conducted vascular reactivity experiments on endothelium-denuded basilar rings. The concentrations of iron (Fe) and ruthenium (Ru) complex were analyzed in basilar artery lysates after incubation with NO donors by mass spectrometry. We also evaluated the NO released from SNP and Terpy by using confocal microscopy. Interestingly, Terpy did not induce relaxation of the basilar artery. SNP induced relaxation in a concentration-dependent way. NO donors cross the membrane of vascular smooth muscle and entered the cell. In spite of its permeability, Terpy did not release NO in the basilar artery. Otherwise, SNP released NO in the basilar artery cells cytoplasm. Taken together, our results demonstrate that the new NO donor (Terpy) failed to release NO and to induce relaxation in the basilar artery. The NO donor SNP induces vascular relaxation due to NO release in the vascular smooth muscle cells.     

猪十二指肠类肝素对动脉平滑肌细胞增殖的影响

目的　研究类肝素对平滑肌细胞增殖的影响及其机制。方法　分别以结晶紫和MTT染色、透射电镜及流式细胞仪等方法,观察类肝素对平滑肌细胞增殖,细胞形态,细胞内α-肌动蛋白含量及原癌基因c-myc,c-fos表达的影响。结果　类肝素0.2,0.4及0.8 mg.mL^-1可以抑制10%小牛血清所致平滑肌细胞增殖,类肝素0.8 mg.mL^-1可以使细胞维持类似收缩型的形态学表现,使细胞内α-actin含量增加,c-myc, c-fos原癌基因表达减少。结论　类肝素可以抑制平滑肌细胞增殖,其机制可能与抑制细胞表型转化,抑制细胞内原癌基因表达有关。     

Selectivity of phenytoin and dihydropyridine calcium channel blockers for relaxation of the basilar artery

We addressed the questions of whether or not phenytoin is a direct vasodilator and if it is selective for brain blood vessels, by studying the relaxant effects of phenytoin on isolated segments of canine basilar, femoral, and brachial arteries. Two dihydropyridine calcium channel blockers, nifedipine and PY 108-068, were also studied for comparison with phenytoin and to test for cerebral selectivity. Blood vessels were contracted with K+, prostaglandin F2 alpha, or serotonin. Phenytoin relaxed the basilar artery with low potency (pD2, 4.71 +/- 0.14) and moderate selectivity. Phenytoin also antagonized Bay K 8644 contractions of basilar artery in a noncompetitive manner. Basilar arteries contracted with 60 mM K+ were the most sensitive to nifedipine (pD2, 8.72 +/- 0.18), followed by the mesenteric (pD2, 8.24 +/- 0.07), femoral (pD2, 8.04 +/- 0.18), and brachial (pD2, 7.66 +/- 0.23) arteries. A similar pattern was observed in potassium-depolarized arteries relaxed by PY 108-068. The calcium dependence of contraction was studied using intact muscles depolarized in 60 mM K+ as well as chemically skinned basilar artery. Mean pD2 values for Ca2+-induced contractions of intact, depolarized arteries were not different (basilar, 4.15 +/- 0.13; mesenteric, 4.04 +/- 0.07; femoral, 4.24 +/- 0.11). The mean Ca2+ EC50 of chemically skinned basilar arteries was 8.7 X 10(-7) M, which is similar to the Ca2+ sensitivity of other skinned smooth muscles. The beneficial effect of phenytoin in treating cerebral ischemia may be due in part to relaxation of vascular smooth muscle. The dihydropyridines were potent smooth muscle relaxants with selectivity for the basilar artery.(ABSTRACT TRUNCATED AT 250 WORDS)     

A novel approach for the determination of contractile and calcium responses of the basilar artery employing real-time confocal laser microscopy

INTRODUCTION: Intracellular calcium concentration ([Ca(2+)](i)) modifications in endothelial and smooth muscle cells represent a key element in the pathogenesis of cerebral artery vasospasm. Therefore, the present study documented potential application of confocal laser microscopy in the determination of contractile and [Ca(2+)](i) responses in basilar artery. METHODS: Experiments were performed on the rat isolated basilar artery. Changes in [Ca(2+)](i) were determined by ratiometry involving Fluo-4/AM and Fura Red/AM. Contractile function was calculated from the change in fluorescent area by Fluo-4/AM. RESULTS: KCl (50 mM) elicited an increase in [Ca(2+)](i) and contraction in basilar artery; moreover, nearly well maintained responses were evident for at least 120 min following the first application. 10 microM 5-hydroxytryptamine (5-HT), 10 microM alpha,beta-methyleneadenosine 5'-triphosphate (alpha,beta-meATP) and 10 nM vasopressin (VP) also induced increases in [Ca(2+)](i) and contraction dose-dependently. Additionally, 10 microM acetylcholine elicited a transient [Ca(2+)](i) decrease and sustained relaxation. In individual cells, rhythmical changes in [Ca(2+)](i) were observed after 10 microM 5-HT. VP (10 nM) evoked modest Ca(2+) oscillation in individual cells; however, Ca(2+) oscillation was not detectable with 10 microM alpha,beta-meATP. DISCUSSION: These results indicate that this method offers reproducibility and quantifiable effects. Imaging technology may therefore be applied to the estimation of [Ca(2+)](i) responses at the tissue level as well as at the level of the individual cell. Thus, confocal laser microscopy is a suitable tool for estimation of small artery function.     

Pharmacological implications of cellular localization of α1-adrenoceptors in native smooth muscle cells

1 This study examines the cellular localization of α₁-adrenoceptors and demonstrates that binding to intracellular receptive binding sites in native smooth muscle cells may influence the pharmacological profile of agonists or antagonists. The example tissue studied was rat basilar artery. 2 An α₁-adrenoceptor antagonist and fluorescent analogue of prazosin, BODIPY-FL prazosin (QAPB) allowed visualization, with high resolution, of both plasma membrane and cytosolic binding sites on live native cells, as previously shown in cells harbouring recombinant receptors. QAPB-associated fluorescence binding was both time- and concentration- dependent in rat basilar smooth muscle cells and affinity for α₁-adrenoceptors was calculated from specific binding curves as 1.1 nM. 3 Concentration-dependent binding of QAPB detected in smooth muscle cells dissociated from rat basilar arteries was composed of diffuse and clustered fluorescence. Visually the diffuse component of fluorescence was the more evident up to a concentration of 5 nM QAPB. Confocal visualization of an optical section through the cell showed that the clustered component was located mainly intracellularly. In rat basilar artery smooth muscle cells the intracellular binding sites were located in close proximity to the nuclear membrane. 4 3D models of QAPB-associated fluorescence demonstrate that a high proportion of effective binding sites are intracellular, showing not only that a high proportion of receptors are located inside the cell but also that in this location they can bind ligands. This has implications for. pharmacological analysis in relation to the consequences of intracellular binding per se and for differential effects upon the pharmacology of particular ligands according to whether they can enter the cell.     

Vasorelaxant properties of norbormide, a selective vasoconstrictor agent for the rat microvasculature.

1. The effects of norbormide on the contractility of endothelium-deprived rat, guinea-pig, mouse, and human artery rings, and of freshly isolated smooth muscle cells of rat caudal artery were investigated. In addition, the effect of norbormide on intracellular calcium levels of A7r5 cells was evaluated. 2. In resting rat mesenteric, renal, and caudal arteries, norbormide (0.5-50 microM) induced a concentration-dependent contractile effect. In rat caudal artery, the contraction was very slowly reversible on washing, completely abolished in the absence of extracellular calcium, and antagonized by high concentrations (10-800 microM) of verapamil. The norbormide effect persisted upon removal of either extracellular Na+ or K+. The contractile effect of norbormide was observed also in single, freshly isolated smooth muscle cells from rat caudal artery. 3. In resting rat and guinea-pig aortae, guinea-pig mesenteric artery, mouse caudal artery, and human subcutaneous resistance arteries, norbormide did not induce contraction. When these vessels were contracted by 80 mM KCl, norbormide (10-100 microM) caused relaxation. Norbormide inhibited the response to Ca2+ of rat aorta incubated in 80 mM KCl/Ca2(+)-free medium. Norbormide (up to 100 microM) was ineffective in phenylephrine-contracted guinea-pig and rat aorta. 4. In A7r5 cells, a cell line from rat aorta, norbormide prevented high K(+)- but not 5-hydroxytryptamine-induced intracellular calcium transients. 5. These findings indicate that in vitro, norbormide induces a myogenic contraction, selective for the rat small vessels, by promoting calcium entry in smooth muscle cells, presumably through calcium channels. In rat aorta and arteries from other mammals, norbormide behaves like a calcium channel entry blocker.     

Heterogeneity in the distribution of vascular gap junctions and connexins: implications for function

1. Gap junctions, which are comprised of members of a family of membrane proteins called connexins (Cx), permit the transfer of electrical and chemical information between adjacent cells in a wide variety of tissues. The aim of the present study was to compare the expression of Cx37, 40 and 43 in the smooth muscle and endothelium of a large elastic artery and two smaller muscular arteries of the rat. Serial section electron microscopy was also used to determine the presence of pentalaminar gap junctions in the smooth muscle and the incidence of myoendothelial gap junctions between the smooth muscle and endothelial cells in muscular arteries of different size. 2. Using immunohistochemistry, Cx37, 40 and 43 were found in the endothelium of the aorta, caudal and basilar arteries, with Cx43 being the least abundant. Connexin 43 was readily observed throughout the muscle layers of the aorta, but was not detected in the media of the caudal or basilar arteries. Connexin 40 was not detected in the media of any of the arteries, while very fine punctate staining was observed with Cx37 antibodies in the media of the caudal and basilar arteries, but not in the aorta. 3. Real-time polymerase chain reaction showed that the expression of mRNA for Cx43 was 15-fold greater in the aorta than in the caudal artery of the rat. 4. At the ultrastructural level, small pentalaminar gap junctions (< 100 nm) were found between the fine processes of adjacent smooth muscle cells and also between the smooth muscle and endothelial cells. The incidence of myoendothelial gap junctions in the mesenteric vascular bed and in the caudal artery increased as vessel size decreased. 5. In summary, heterogeneity exists within the vascular system with regard to the distribution of gap junctions and their constituent Cx. Such variation will have important consequences for the coordination and propagation of vascular responses. In muscular arteries, in comparison with elastic arteries, Cx37 may be more important than Cx43 for cell coupling within the smooth muscle layers. The correlation between the incidence of myoendothelial gap junctions and the role of endothelium-derived hyperpolarizing factor, relative to nitric oxide, in vasodilatory responses suggests that myoendothelial gap junctions play an important physiological role in the regulation of vascular tone.