高浓度葡萄糖抑制兔胸主动脉内皮依赖的血管舒张(英文)

目的:研究高浓度葡萄糖是否能抑制兔胸主动脉内皮依赖的血管舒张以及可能的机制。方法:利用器官组织浴动脉环法测定血管张力,观察去除内皮、NO合酶抑制剂L-NMMA,不同浓度的葡萄糖对乙酰胆碱(ACh)产生的内皮依赖的和硝普钠(SNP)产生的非内皮依赖的血管舒张功能的影响以及维生素C和膜渗透性抗氧化剂MnTMPyP对高浓度葡萄糖作用的影响。结果:ACh和SNP均产生浓度依赖的血管舒张效应,高浓度葡萄糖明显抑制ACh产生的血管舒张,而对SNP的作用无明显影响,维生素C和MnTMPyP不能逆转高浓度葡萄糖对ACh产生的血管舒张的抑制作用。结论:高浓度葡萄糖抑制内皮依赖的血管舒张,这种作用不是通过增加氧自由基的产生介导的。     

植物雌激素白藜芦醇和根皮素对家兔离体主动脉收缩反应的影响(英文)

目的探讨植物雌激素白藜芦醇和根皮素对离体主动脉血管收缩的舒张作用特点是否同雌激素以及有关的作用机制。方法将家兔离体主动脉平滑肌条置于灌流肌槽中,记录其等长张力变化。结果白藜芦醇和根皮素可明显抑制离体血管对去甲肾上腺素(NE)、KCl和CaCl2的浓度依赖性收缩反应,使其量效曲线明显右移, pD2′值分别为2.89,3.34, 3.37和3.23, 3.52, 3.77;对KCl预收缩血管条具有浓度依赖性的舒张效应。去除血管内皮、Nω-L-硝基精氨酸(L-NNA)或亚甲蓝对白藜芦醇舒张血管作用具有明显的抑制作用,但对根皮素诱发的血管舒张无明显影响。吲哚美辛和普萘洛尔温育后,对二者的舒血管作用均无明显影响。在无钙Krebs液(含0.01 mmol·L-1EGTA)中,白藜芦醇和根皮素可抑制NE诱发的由肌细胞内钙释放引起的Ⅰ相收缩,但不影响CaCl2诱发的由肌细胞外钙内流引起的Ⅱ相收缩。结论白藜芦醇和根皮素对离体主动脉血管的舒张作用可能与其抑制钙离子内流及细胞内钙释放有关;另外白藜芦醇的舒张作用部分与内皮细胞有关,但根皮素的舒血管作用与内皮细胞无关。     

高浓度葡萄糖抑制兔胸主动脉内依赖的血管舒张

目的：研究高浓度葡萄糖是否能抑制兔胸主动脉内皮依赖的血管舒张以及可能的机制。方法：利用器官组织浴动脉环法测定血管张力,观察去除内皮、NO合酶抑制剂L－NMMA,不同浓度的葡萄糖对乙酰胆碱（ACh)产生的内皮依赖的和硝普钠（SNP）产生的非内皮依赖的血管舒张功能的影响以及维生素C和膜渗透性抗氧化剂MnTMPyP对高浓度葡萄糖作用的影响。结果：ACh和SNP均产生浓度依赖的血管舒张效应,高浓度葡萄糖明显抑制ACh产生的血和舒张,而对SNP的作用无明显影响,维生素C和MnTMPyP不能逆转高浓度葡萄糖对ACh产生的血管舒张的抑制作用。结论：高浓度葡萄糖抑制内皮依赖的血管舒张,这种作用不是通过增加氧自由基的产生介导的。     

自由基使血管舒张因子从主动脉内皮细胞与平滑肌细胞中释放(英文)

电解Krebs液产生自由基,灌流通过有内皮细胞或去内皮细胞的家兔主动脉;或通过生长在微粒上的小牛主动脉内皮细胞柱;用淋浴生物检定法均检测出由血管内皮细胞或血管平滑肌释放出的血管舒张因子。这种血管舒张因子与用ADP通过血管内皮细胞柱释放的血管内皮舒张因子(EDRF)有类似的性质,即作用时间短暂,并可被同时灌注N-硝基-L-精氨酸(为EDRF合成拮抗剂)或血红蛋白(为EDRF清除剂)所减弱。在去内皮细胞的主动脉,ADP的释放作用消失,但自由基的释放作用仍存在,表明血管平滑肌也可释放,因羟自由基消除剂水杨酸钠能明显减弱电解产生的自由基的这种释放作用,故推测电解产生的羟自由基在释放血管舒张因子中起主要作用。     

氧张力变化对离体兔主动脉内皮细胞释放物质的释放模式和状态的作用(英文)

AIM: To Observe the effect of change in oxygen tensionon the release pattern and nature of endothelium-derivedsubstances in isolated rabbit aorta. METHODS: Iso-metric contractions and relaxations in isolated rabbit stripwere observed in response to changes in oxygen tensionand effect of various drugs was noted on them. RE-SULTS: Change in oxygen tension from high [po_2=(618.9±0.4) mmHg; 1 mmHg= 133.3 Pa] to low[Po_2= (117.6± 0.6) mmHg] was observed to convert     

利多卡因对离体兔胸主动脉环收缩的影响

以维拉帕米(verapamil,Ver)作对照,在离体兔胸主动脉环上对利多卡因(lidocaine,Lid)松弛血管平滑肌的机理进行了探讨。Lid对高K+去极化主动脉环收缩和Ver一样有明显的松弛作用。对去甲肾上腺素(NA)引起主动脉环收缩的试验中,Lid和Ver都能抑制细胞内Ca²⁺的释放,但不抑制外Ca²⁺内流。Lid对KCl,NA量-效曲线产生非平行右移,最大反应压低,且对KCl的抑制作用大于NA,说明Lid对PDC通道有选择性阻滞作用,而对ROC通道相对不敏感。对CaCl₂量-效曲线也产生非平行右移且最大反应压低,呈非竞争性拮抗。初步提示Lid在一定浓度下有拮抗Ca²⁺的作用,这种作用为非特异性,是松弛血管平滑肌机理之一。     

粉防己碱对Bay k 8644引起兔离体主动脉条收缩的抑制作用

In the presence of KCl 19 mmol.L-1, calcium agonist Bay k 8644 0.47 mumol.L-1 elicited a strong contraction of isolated rabbit aortic strips, and this contraction was concentration-dependently inhibited by tetrandrine; but this antagonism was noncompetitive. Calcium ionophore calcimycin evoked contraction was markedly depressed by tetrandrine. The results suggested that tetrandrine might not only inhibit transmembrane influx of calcium via potential-dependent channels but also interfere with other processes related to calcium.     

Effects of lysophosphatidylcholine and endothelium on isolated rabbit aortic ring contraction by serotonin

在离体兔胸主动脉环模型上观察溶血性磷脂酰胆碱（ＬＰＣ）促血管收缩作用的机理以及血管内皮对ＬＰＣ促血管收缩作用的影响．１０μｍｏｌ·Ｌ－１ＬＰＣ预温育３０ｍｉｎ可显著增强兔胸主动脉环对５－羟色胺（５－ＨＴ）的收缩反应,使０．１μｍｏｌ·Ｌ－１５－ＨＴ诱导的峰值张力增加到约２．５倍,ＥＣ５０降低,收缩曲线左移．而蛋白激酶Ｃ（ＰＫＣ）抑制剂显形孢菌素（ｓｔａｕｒｏｓｐｏｒｉｎｅ,１００ｎｍｏｌ·Ｌ－１）能抑制ＬＰＣ的促血管收缩作用,ＥＣ５０恢复;去除血管内皮或加入１００μｍｏｌ·Ｌ－１左旋单甲基精氨酸（Ｌ－ＮＭＭＡ）预处理均可显著增强ＬＰＣ的促血管收缩作用,Ｌ－ＮＭＭＡ的作用更强（Ｐ＜０．００１）．结果提示,ＬＰＣ可能通过ＰＫＣ途径促进５－ＨＴ介导的血管收缩,血管内皮可能在其中起调控作用．     

藻酸双酯钠对大鼠离体去内皮胸主动脉环的舒缩作用

目的:观察藻酸双酯钠(polysaccharide sulfate,PSS)对离体大鼠胸主动脉平滑肌舒缩的影响。方法:采用大鼠离体去内皮主动脉环灌流模型,观察不同浓度PSS(5×10-2～5×102 mg.L-1)对基础状态及氯化钾(KCl)、去氧肾上腺素(PE)等试剂的血管收缩效应的影响。结果:不同浓度PSS对基础状态、KCl或PE的去内皮血管环收缩效应无明显影响。PSS(5×102 mg.L-1)对内钙释放及外钙内流引起的血管收缩效应无明显影响。结论:在5×10-2～5×102 mg.L-1浓度范围内,PSS对离体血管平滑肌没有明显舒缩作用。     

Phytoestrogen genistein decreases contractile response of aortic artery in vitro and arterial blood pressure in vivo

INTRODUCTION Phytoestrogens are naturally found in many plants,particularly soy beans, and they are defined as plantsubstances that are structurally or functionally similarto estradiol[1,2]. Genistein, a phytoestrogen, may haveestrogenic cardioprotective actions[3]. Epidemiologicaldata suggest a reduction in the incidence of coronaryheart disease in humans who have a high intake ofphytoestrogens[4]. Increased plasma levels of thephytoestrogen genistein are suggested as an explana-tion for…     

Effect of calcium on the vascular contraction induced by cobra venom cardiotoxin

1. The cytotoxic effects of cardiotoxin (CTX) purified from Cobra venom were tested in endothelium-denuded rat aortic ring preparations in tissue organ baths and the effect of extracellular Ca2+ on the cytotoxic effect of CTX was investigated using a digital dynamic calcium imaging technique. 2. At 10 micromol/L, CTX induced a slowly developing and sustained contraction that amounted to approximately 50% of the maximal contraction induced by 80 mmol/L KCl. At high concentrations (> 15 micromol/L), CTX caused irreversible damage to the smooth muscle contractile function. However, washout of CTX at its peak contraction did not affect the subsequent contraction to either KCl or phenylephrine. 3. Contraction induced by CTX was dependent on the Ca2+ concentration in the external solution. A maximal contractile response to CTX was obtained in medium containing 1-2.5 mmol/L Ca2+. This contractile response induced by CTX decreased with higher Ca2+ concentrations and was completely diminished when 7 mmol/L Ca2+, 3 mmol/L Ni2+ or 30 micromol/L tetrandrine (a non-selective calcium channel blocker) was present in the external solution before addition of CTX to the bath. 4. The above observations were supported by the calcium imaging work performed with cultured aortic smooth muscle cells from Wistar-Kyoto rats, in which CTX was shown to induce the elevation of cytosolic Ca2+ in the presence, but not in the absence, of 2.5 mmol/L extracellular Ca2+. Increasing the extracellular Ca2+ concentration to 7 mmol/L, the addition of 3 mmol/L Ni2+ or inclusion of 30 micro mol/L tetrandrine inhibited the elevation of cytosolic Ca2+ induced by CTX. 5. These results suggest that: (i) a CTX-sensitive internal calcium store does not exist in rat aortic smooth muscle; (ii) the contractile effect CTX is associated with a Ca2+ influx process; and (iii) CTX interacts extracellularly with the plasma membrane at the level of the calcium channels, as well as anionic sites to which Ca2+ and other inorganic cations bind.     

钾通道开放剂对培养兔主动脉平滑肌细胞增殖的抑制作用

钾通道开放剂对培养兔主动脉平滑肌细胞增殖的抑制作用１史道华２，郭兆贵（湖南医科大学药理研究室，长沙４１００７８，中国）关键词血管平滑肌；胸主动脉；培养的细胞；细胞分裂；苯福林；钾通道目的：探讨吡那地尔（Ｐｉｎ），尼可地尔（Ｎｉｃ），ＲＰ４９３５６（Ｒ...     

西洋参茎叶皂甙对离体家兔胸主动脉条的作用

西洋参茎叶皂甙对离体家兔胸主动脉条的作用吴捷，于晓江，刘传镐（西安医科大学临床药理研究所，西安７１００６１）西洋参茎叶皂甙（ｓａｐｏｎｉｎｓｏｆＰａｎａｘｑｕｉｎｑｕｅ－ｆｏｌｉｕｍｌｅａｆａｎｄｓｔｅｍ，ＳＰＱ）系从西洋参地上部分提取的总皂甙，具有...     

Relaxation effects of matrine on guinea-pig aortic smooth muscles

Objective The present in vivo study was undertaken to determine whether matrine,a kind of traditional Chinese medicinal alkaloid,would relax the isolated guinea pig aortic smooth muscles,if so,to investigate the mechanism involved.Methods The concentration-dependent relaxation response to matrine was studied in phenylephrine or potassium chloride precontracted guinea pig aortic rings.Results Matrine(1×10-4 M-3.3×10-3 M)relaxed the endothelium denuded aortic rings precontracted submaximally with phenylephrine,in a concentration-dependent manner,and it's preincubation(3.3×10-3 M)produced a significant rightward shift in the phenylephrine dose-response curve,but had no effects on the potassium chloride-induced contraction.The anticontractile effect of matrine was not reduced by the highly selective ATP-dependent K+ channel blocker glibenclamide(10-5 M),the non-selective K+ channel blocker tetraethylammonium(10-3 M),as well as the β-antagonist propranolol(10-5 M).In either "normal" or "Ca2+-free" bathing medium,the phenylephrine-induced contraction was attenuated by matrine(3.3×10-3 M),indicating the vasorelaxation was due to inhibit of intracellular and extracellular Ca2+ mobilization.Conclusions The results obtained clearly demonstrated that matrine inhibits phenylephrine-induced contractions by inhibiting activation of α-adrenoceptor and interfering with both the release of intracellular Ca2+ and the influx of extracellular Ca2+.     

麝香保心丸对大鼠离体主动脉环的药理作用

目的：研究麝香保心丸的舒张血管作用及可能的机制。方法：将离体大鼠动脉环随机分成正常组，去内皮组２组（共为６对动脉环，组内比较用自身对照，组间比较用配对对照）。用去甲肾上腺素诱导动脉环收缩后，加入麝香保心丸，记录反应。结果：麝香保心丸对正常组，去内皮组动脉环均有舒张作用（Ｐ＜０．０１），其效应呈剂量依赖；且其对正常组的舒张作用较去内皮组强（Ｐ＜０．０１）。结论：麝香保心丸具有舒张血管的效应，其机制可能有直接及内皮依赖的舒张血管２种作用。