补阳还五汤对动脉粥样硬化大鼠主动脉超微结构的影响

目的观察补阳还五汤(BYHWT)对动脉粥样硬化(AS)大鼠主动脉超微结构的影响。方法用高脂饲料加维生素D3的方法建立AS大鼠模型。将40只AS大鼠随机分为模型组(0.9%Na Cl 10 m L·kg^-1)、对照组(辛伐他汀0.6mg·kg^-1)和低、高剂量实验组(BYHWT 10,20 g·kg^-1),每组10只;另取20只正常大鼠随机分为空白组(0.9%Na Cl 10 m L·kg^-1)和预防组(BYHWT 10g·kg^-1,造模的同时给药),每组10只。造模成功后,干预28 d。在透射电镜下观察大鼠主动脉内皮细胞、平滑肌细胞的超微结构。结果高剂量实验组、对照组、预防组的病变均明显轻于模型组,内皮细胞大多形态正常,较完整,内弹力膜较均匀、平直,平滑肌细胞排列整齐。模型组内皮及内皮下层可见到大量泡沫样细胞,有纤维粥样斑块形成,内弹力膜厚薄不一,甚至缺失,平滑肌细胞胶原纤维增生,管壁结构紊乱,胞浆含较多脂质。结论补阳还五汤可改善或纠正AS大鼠模型血管内皮细胞及平滑肌细胞异常的超微结构。     

2型糖尿病大血管病变与内脂素的关系探讨及降糖调脂灵的干预作用

目的观察降糖调脂灵保护2型糖尿病大血管病变与内脂素的关系。方法 10只健康成年♂Wistar大鼠作为正常对照组,喂以标准饲料不做处理;50只健康♂大鼠通过高糖高脂饲料喂养+腹腔注射链脲佐菌素诱发糖尿病,随机选取30只成模大鼠分为3组:糖尿病模型组(n=10,灌胃,等量生理盐水)、二甲双胍组(n=10,灌胃,二甲双胍200 mg·kg 1·d 1)、降糖调脂灵组(n=10,灌胃,降糖调脂灵浓缩液5 mL·kg 1·d 1),继续喂以高糖高脂饲料。12周后取血测血糖、血脂、单核细胞趋化因子和细胞间黏附分子的含量;Western-blot法检测血清内脂素表达水平;光镜观察主动脉壁情况,透射电镜观察主动脉超微结构改变。结果降糖调脂灵组血糖、血脂、单核细胞趋化因子和细胞间黏附分子的含量降低,内脂素表达减少,主动脉内皮细胞损坏减轻。结论降糖调脂灵保护T2DM大血管病变,可能与抑制内脂素表达,降低血糖、血脂,减轻炎症反应有关。     

实验性急性肺血栓栓塞症肺动脉血管重构及意义

目的：探讨急性肺血栓栓塞症肺动脉血管重构及其临床意义。方法：取栓塞3～24h后的急性肺血栓栓塞症动物模型的栓塞段肺动脉，同时取正常肺动脉设实验对照组，固定液固定后送检。结果：正常肺动脉内皮细胞完整，未见平滑肌细胞迁移，肌层平滑肌呈层状，多为收缩型；肺栓塞后，肺动脉内皮细胞脱落，中层平滑肌细胞向内皮迁移，可见较多的合成型平滑肌细胞，内皮下可见类凋亡平滑肌细胞。结论：急性肺栓塞后，栓塞段肺动脉局部发生血管重构．对肺动脉高压的产生可能起着一定作用。     

实验性糖尿病大鼠主动脉的早期改变

观察了链脲佐菌素 ( streptozotocin STZ)致实验性糖尿病大鼠主动脉早期超微结构及转化生长因子β1 ( TGFβ1 )的改变 ,并探讨了糖尿病动脉粥样硬化 ( AS)的发病机制。结果显示 ,STZ糖尿病大鼠出现持续高血糖、高血脂 ,主动脉早期出现内膜增厚 ,内皮下间隙变宽 ,内弹力板破坏 ,内膜和中膜浅层平滑肌细胞增生及部分向内膜迁移。免疫组化显示糖尿病大鼠主动脉内 TGF-β1 表达明显高于正常大鼠。     

兔、豚鼠动脉粥样硬化模型的建立

目的：建立兔、豚鼠动脉粥样硬化模型,探讨模型形成机制并进行比较.方法：用高脂饲料喂养法建立兔、豚鼠动脉粥样硬化模型.高脂饲料喂养,检测血清甘油三脂（TG）、总胆固醇（TC）、高密度脂蛋白（HDL）和低密度脂蛋白胆固醇（LDL）、一氧化氮（NO）、肿瘤坏死因子（TNF-α）的含量,动脉病理组织学检测.结果：兔模型组TC、TG、LDL、NO、TNF-α升高,HDL降低,与正常组比较有显著性差异（P＜0.05,0.01）.豚鼠TC、TG、LDL、HDL、NO、TNF-α升高,与正常组比较有显著性差异（P＜0.05,0.01）.两种动物模型组组动脉病理检测均不同程度出现动脉内膜明显增厚,纤维隆起明显,内皮细胞肿胀、变性、部分缺失,内弹力膜断裂、模糊,中膜增厚伴平滑肌细胞增生,胞体变大,排列紊乱,内膜及中膜均可见巨噬细胞.结论：兔动脉粥样硬化诱导时间比豚鼠短,成模率比豚鼠高,病变更显著.     

高血脂对脉络膜血管超微结构的影响研究

目的 揭示高血脂对动物脉络膜血管组织学改变的影响,初步探讨高血脂在年龄相关性黄斑变性患者脉络膜新生血管形成中的作用.方法 36只新西兰大白兔随机分为正常对照组与实验组,分别喂养普通饲料与高脂饲料.分别于1 m、2 m、3 m后观察眼底改变,酶法测定血清中总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)及高密度脂蛋白胆固醇(HDL-C),应用透射电镜观察脉络膜组织学改变.结果 实验组动物的TC、TG、LDL-C水平与对照组相比均具有统计学意义.脉络膜血管超微结构:对照组未见明显异常;实验组出现血管内皮细胞肿胀、变形,细胞核异型,细胞间连接破坏;基底膜节段性增厚;管腔变窄,甚至闭塞;管壁脂滴增多,见泡沫细胞.结论 高血脂可能通过对脉络膜血管内皮细胞的直接损害影响年龄相关性黄斑变性的发生和发展.     

三七皂苷R1调节炎性T细胞亚群保护血管内皮的实验研究

目的探讨炎性T细胞亚群在胶原酶诱导的血管内皮损伤早期的变化状态及三七皂苷R1的保护作用机制。方法采用扫描电镜观察ApoE-/-小鼠动脉内皮损伤程度;流式细胞术检测小鼠外周血中CD62Phi、CD62P+CD62E+脱落内皮细胞的比例;胞内外因子染色法检测炎性T细胞亚群分泌TNF-α、IL-17的水平。结果扫描电镜下,内皮损伤模型组小鼠血管内膜受损明显,内皮脱落面积明显增加,实验组经三七皂苷R1处理后血管内皮偶有脱落(P均<0.05);另外,模型组脱落内皮细胞CD62Phi、CD62P+CD62E+比例明显高于正常对照组,同时,T细胞分泌TNF-α、IL-17的能力明显升高,而实验组脱落内皮细胞比例明显低于模型组,T细胞分泌IL-17的比例下降(P均<0.05)。结论 Th17细胞亚群比例升高与血管内皮早期损伤密切相关,三七皂苷R1在保护血管内皮的同时,可选择性地下调Th17细胞亚群比例。     

高脂饮食对大鼠血管内皮功能及腹主动脉形态学的影响

目的观察高脂饮食对大鼠血管内皮功能和腹主动脉形态学的影响。方法选用健康SD雄性大鼠16只,体质量150～180g,随机分为正常对照组和高脂饮食组,每组8只。正常对照组用普通饲料喂养,高脂饮食组用高脂饲料喂养4周。观察高脂饮食对大鼠血浆血管紧张素Ⅱ（angiotensinⅡ,AngⅡ）、血浆内皮素（endothelin,ET）和血清一氧化氮（nitrogen monoxide,NO）的影响,以及腹主动脉形态学变化。结果4周后高脂饮食组血浆血管紧张素Ⅱ、血浆内皮素与正常对照组相比明显升高（P〈0.01）,血清NO与正常对照组相比明显降低（P〈0.01）;光学显微镜、透射电镜下见高脂饮食组腹主动脉壁结构异常。结论高脂饮食可致大鼠血管内皮功能障碍和腹主动脉形态学改变。     

去势雌性大鼠主动脉平滑肌细胞雌激素受体的变化

目的：探讨绝经后血管平滑肌细胞雌激素受体的变化。方法：采用切除双侧卵巢、高脂饲料喂养造模大鼠，观察去势雌性大鼠血脂的变化，并应用免疫组化法(SP法)测定主动脉平滑肌细胞雌激素受体变化。结果：去势雌性大鼠血脂代谢紊乱，主动脉平滑肌细胞雌激素受体水平下降。结论：绝经后女性心血管疾病发病率与雌激素受体水平下降有关。     

山楂叶含药血清对高脂血清诱导单核细胞与血管内皮细胞黏附能力的影响

目的研究山楂叶含药血清对高脂血清诱导的单核细胞与血管内皮细胞黏附能力及黏附分子表达的影响,并探讨其作用机制。方法采用虎红染色法检测药物血清对高脂诱导的人脐静脉内皮细胞(human umbilical vascular endothelial cells,HUVEC)和单核细胞株THP-1黏附的作用;用细胞ELISA法检测HUVEC表面细胞间黏附分子-1(intercelluar adhesion molecule-1,ICAM-1)、血管细胞黏附分子-1(vascular cellular adhesion molecule-1,VCAM-1)、P-选择素(P-selectin)的表达。结果山楂叶能抑制高脂诱导的HUVEC与THP-1的黏附,并下调HUVEC表面ICAM-1、VCAM-1、P-se-lectin的表达。结论山楂叶防治高脂血症的机制之一可能是下调血管内皮细胞黏附分子的表达,减少单核细胞与内皮细胞的黏附,从而抑制单核细胞迁移至血管内膜形成泡沫细胞而实现。     

Comparative toxicity of the cardiovascular toxin allylamine to porcine aortic smooth muscle and endothelial cells

This study supports a recent hypothesis that the cardiovascular toxin, allylamine, is toxic to smooth muscle cells of large elastic arteries (aorta). Cultures of the porcine aortic smooth muscle, endothelial, and fibroblastic cells were exposed to varying concentrations of allylamine ranging from 5 microM to 340 microM. Monitored cytotoxic and cytolytic activities demonstrated that final concentrations of 60 microM allylamine decreased cell population viability of smooth muscle cells as much as 50%. Viability decreased approximately linearly with increasing concentrations of allylamine including spontaneous lysing of smooth muscle cells at 90 microM. Endothelial cells were more resistant to lower concentrations of allylamine requiring 90 microM to decrease cell population viability by 50%. In contrast, fibroblastic cells were very resistant to lower concentrations of allylamine. The specific lytic response of these cells in culture, measured by release of [3H]thymidine, gave findings parallel to the viability studies, i.e. at 100 microM allylamine smooth muscle cells demonstrated 75% specific lysis while endothelial cells showed 29%. Growth studies of cells surviving an 8-h exposure to allylamine indicate that surviving endothelial cells have better growth characteristics than surviving smooth muscle cells; both cell lines are also apparently injured at concentrations of allylamine much lower than the CT50. These studies show that of the cellular components of the vascular wall, smooth muscle cells appear to be the most sensitive to the toxic effects of allylamine.     

硫酸多糖与动脉粥样硬化

动脉粥样硬化（ＡＳ）的发生、发展是一个十分复杂的病理过程。它涉及到血管内皮细胞（ＥＣ）、平滑肌细胞（ＳＭＣ）、炎性细胞（如单核细胞、巨噬细胞等）、淋巴细胞、血小板等多种细胞及相关细胞因子。许多研究发现硫酸多糖与ＡＳ存在密切的关系。大多报道表明硫酸多糖可保护ＥＣ免受各种刺激因子的损伤作用,从而阻断ＡＳ形成的起始环节;另外,硫酸多糖也可通过抑制ＶＳＭＣ增殖、迁移;减少炎性细胞、淋巴细胞、血小板等粘附、聚集到血管内膜;抑制补体的激活等多种途径来达到抗ＡＳ目的。但也有文献报道部分硫酸多糖反而促进ＡＳ形成。而且硫酸多糖的抗ＡＳ活性与其分子结构有关,所以ＡＳ与硫酸多糖的关系是一直存在争议的问题。     

阿司匹林抗动脉粥样硬化作用及机制

目的观察阿司匹林对大鼠动脉粥样硬化（AS）的预防性干预作用,并探讨阿司匹林抗AS的作用及其可能的作用机制。方法采用高脂饮食方法建立大鼠AS模型。放射免疫法检测血脂;通过荧光分光光度计检测胸主动脉和腹主动脉组织内糖基化终产物（AGEs）的含量;采用定量病理学测量大鼠主动脉斑块面积、内膜面积、斑块面积/内膜面积比、血管周长;光学显微镜下观察主动脉壁粥样硬化的改变。结果模型组（model）的血脂检测、AGEs含量、形态学及病理学与普通饲料喂养组比较差异有统计学意义（P〈0.05）,证实造模成功。阿司匹林高低剂量组（AH组、AL组）与模型组的总胆固醇差异无统计学意义（P〉0.05）;AL组的主动脉组织内AGEs含量较模型组显著降低（P〈0.05）;AL、AH组均可见散在的斑块生长、血管内膜光滑,与模型组比较,AL组、AH组间的斑块面积、斑块面积/内膜面积变化不大（P〉0.05）,但有下降趋势。光学显微镜下观察：模型组主动脉内膜结构不完整、中膜明显钙化、胶原增生;AL组、AH组主动脉内皮结构完整,中膜钙化程度较模型组减轻。结论阿司匹林不影响大鼠的血脂水平,但可减轻血管壁钙化,延缓AS斑块的形成。     

Endothelium-dependent contractions in SHR: a tale of prostanoid TP and IP receptors

In the aorta of spontaneously hypertensive rats (SHR), the endothelial dysfunction is due to the release of endothelium-derived contracting factors (EDCFs) that counteract the vasodilator effect of nitric oxide, with no or minor alteration of its production. The endothelium-dependent contractions elicited by acetylcholine (ACh) involve an increase in endothelial [Ca²⁺]_i, the production of reactive oxygen species, the activation of endothelial cyclooxygenase-1, the diffusion of EDCF and the subsequent stimulation of smooth muscle cell TP receptors. The EDCFs released by ACh have been identified as PGH₂ and paradoxically prostacyclin. Prostacyclin generally acts as an endothelium-derived vasodilator, which, by stimulating IP receptors, produces hyperpolarization and relaxation of the smooth muscle and inhibits platelet aggregation. In the aorta of SHR and Wistar-Kyoto rats, prostacyclin is the principal metabolite of arachidonic acid released by ACh. However, in SHR aorta, prostacyclin does not produce relaxations but activates the TP receptors on vascular smooth muscle cells and produces contraction. The IP receptor is not functional in the aortic smooth muscle cells of SHR as early as 12 weeks of age, but its activity is not reduced in platelets. Therefore, prostacyclin in the rule protects the vascular wall, but in the SHR aorta it can contribute to endothelial dysfunction. Whether or not prostacyclin plays a detrimental role as an EDCF in other animal models or in human remains to be demonstrated. Nevertheless, because EDCFs converge to activate TP receptors, selective antagonists of this receptor, by preventing endothelium-dependent contractions, curtail the endothelial dysfunction in diseases such as hypertension and diabetes.     

Vasodilatory and anti-inflammatory effects of the 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) via a nitric oxide-cGMP pathway

Vasorelaxant and anti-inflammatory effects of a 1,2,3,4,6-penta-O-galloyl-beta-d-glucose (PGG) isolated from the root barks of Paeonia suffruticosa and possible mechanisms responsible were investigated. PGG induced a concentration-dependent relaxation of the phenylephrine-precontracted rat aorta. This effect disappeared with the removal of functional endothelium. Pretreatment of the aortic tissues with either N(G)-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4]-oxadiazole-[4,3-alpha]-quinoxalin-1-one (ODQ) inhibited the relaxation induced by PGG. Incubation of human umbilical vein endothelial cells (HUVECs) or carotid arteries isolated from rats with PGG increased the production of cGMP in a dose-dependent manner, but this effect was blocked by pretreatment with L-NAME and ODQ, respectively. PGG treatment attenuated tumor necrosis factor-alpha (TNF-alpha)-induced nuclear factor-kappaB (NF-kappaB) p65 translocation in human umbilical vein endothelial cells. In addition, PGG suppressed the expression levels of adhesion molecules including intracellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) induced by TNF-alpha. TNF-alpha-induced monocyte chemoattractant protein-1 (MCP-1) expression was also attenuated by addition of PGG. PGG treatment inhibited cellular adhesion of U937 cells onto human umbilical vein endothelial cells induced by TNF-alpha. Taken together, the present study suggests that PGG dilates vascular smooth muscle and suppresses the vascular inflammatory process via endothelium-dependent nitric oxide (NO)/cGMP signaling.     

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.     

Histamine H1-receptor in endothelial and smooth muscle cells of guinea-pig aorta

The location of histamine H1-receptors in the thoracic aorta of guinea-pigs was studied with a [3H]mepyramine binding assay. [3H]Mepyramine binding studies of whole and rubbed aortas, and of cultured endothelial and smooth muscle cells showed that the Kd values were all in the range 0.53-0.76 nM, but that the Bmax values were 19.1, 10.1, 63.3 and 11.6 fmol/mg protein, respectively. Thus, the whole aorta contained more H1-receptors than the rubbed one (free of endothelium), and cultured endothelial cells contained more H1-receptors than smooth muscle cells. These results indicate that more histamine H1-receptors were concentrated in the endothelial cells than in the smooth muscle cells in guinea-pig aorta.     

Nitric oxide donor molsidomine favors features of atherosclerotic plaque stability during cholesterol lowering in rabbits

Rupture-prone atherosclerotic plaques are characterized by a thin fibrous cap containing numerous macrophage-derived foam cells and few smooth muscle cells (SMC). Decreasing the ratio between macrophages and SMC might favor plaque stabilization. Macrophages expressing inducible nitric oxide (NO) synthase become hypersensitive to killing by exogenous NO donors. Therefore, we investigated in cholesterol-fed rabbits (20 weeks 0.3% cholesterol) the effect of 4 weeks cholesterol withdrawal alone and in combination with the NO donor molsidomine on plaque size, cell composition, superoxide production and extracellular superoxide dismutase (ecSOD) mRNA expression in the atherosclerotic plaques in the aorta. Cholesterol withdrawal alone did not alter atherosclerotic plaque size, the increased superoxide production or the decreased ecSOD mRNA, but led to the formation of a thin subendothelial macrophage-free layer and reduced both vascular cell adhesion molecule-1 expression and cell replication in the luminal part of the plaques. Treatment with molsidomine (1 mg/kg/day) during cholesterol withdrawal did not affect plaque size but increased the thickness of the subendothelial macrophage-free layer consisting of SMC, and normalized both superoxide production and ecSOD mRNA expression. The latter findings demonstrate that molsidomine, when combined with cholesterol lowering, decreases signs of oxidative stress and increases features of stable atherosclerotic plaques.     

普伐他汀对溶血磷脂酰胆碱促血管平滑肌细胞增殖及细胞粘附的影响

目的　探讨羟甲基戊二酰辅酶A还原酶抑制剂普伐他汀对溶血磷脂酰胆碱 (LPC)促血管平滑肌细胞增殖及白细胞与内皮细胞粘附的影响。方法　用MTT法检测LPC对平滑肌细胞增殖的量效和时效关系及普伐他汀对LPC促平滑肌细胞增殖的影响 ;用直接记数法检测LPC诱导中性粒细胞系K5 6 2细胞与人脐静脉内皮细胞系ECV30 4细胞的粘附和普伐他汀对LPC所致白细胞与内皮细胞粘附的影响。结果　用 1～ 10 μmol·L-1LPC孵育血管平滑肌细胞 2 4～ 4 8h后 ,呈时间和剂量依赖性地诱导细胞增殖 ,而用 0 3～ 1mmol·L-1普伐他汀预孵育平滑肌细胞 1h ,再与 3μmol·L-1LPC共孵育 2 4～ 4 8h ,明显地抑制LPC所诱导的细胞增殖 ;用 3μmol·L-1LPC孵育ECV30 4细胞 12h显著增加K5 6 2细胞与ECV30 4细胞的粘附 ,而将ECV30 4细胞用 1mmol·L-1普伐他汀预处理后 ,明显减少白细胞与内皮细胞的粘附。结论　普伐他汀可抑制LPC促血管平滑肌细胞增殖及白细胞与内皮细胞粘附的作用。