瘦素对自发性高血压大鼠血管平滑肌细胞增殖的影响

目的 探讨leptin对自发性高血压大鼠血管平滑肌细胞的增殖影响，并研究leptin b型受体在VSMC中的表达。方法 本文主要采用培养的自发性高血压大鼠（SHR）血管平滑肌细胞（VSMC），研究Leptin受体b(OB-Rb)的mRNA的表达，以及对平滑肌细胞增殖的影响。结果 OB－Rb的mRNA仅在SHR大鼠的平滑肌细胞表达，而没有在正常对照大鼠（WKY）的平滑肌细胞中表达。Leptin仅仅可以刺激SHR大鼠VSMC的DNA合成率的增加而对WKY大鼠的VSMC则无作用。同样，Leptin对VSMC细胞增殖的作用，也仅仅在SHR大鼠可以发现，而WKY大鼠则没有。结论 上述研究的结果显示；高血压时，Leptin是一种对血管平滑肌细胞的增殖因子，也许在高血压的发生，发展过程中起重要的作用。     

卡托普利抑制自发性高血压大鼠血管平滑肌细胞增殖的机制

卡托普利抑制自发性高血压大鼠血管平滑肌细胞增殖的机制王向宇吴可贵晋学庆许昌声王华军肾素－血管紧张素系统（ＲＡＳ）在高血压心血管肥厚中起重要作用。血管紧张素转换酶抑制剂（ＡＣＥＩ）降低血压、逆转心血管肥厚，主要是通过抑制心血管本身ＲＡＳ实现［１］。本实...     

切除血小板源生长因子α受体基因功能结构域对自发性高血压大鼠血管平滑肌细胞生长的影响

目的 探讨切除血小板源生长因子（PDGF）-α受体基因功能结构域对自发性高血压大鼠血管平滑肌细胞（SHR-VSMC）增殖和肥大的影响。方法 采用免疫印迹（Western blot),^3H-TdR及^3H-Leu掺入等方法，观察在SHR及WKY大鼠血管平滑肌细胞中，PDGF-AA和PDGF受体表达的差异性；应用基因重组技术切除PDGF-α受体基因功能结构域后，对PDGF-AA刺激SHR-VSMC增殖和肥大的影响。结果 SHR-VSMC中PDGF-AA和PDGF-α受体蛋白表达较WKY-VSMC明显增加，而PDGF-β受体蛋白表达在SHR-VSMC与WKY-VSMC无明显差异；在不同浓度刺激下，增殖细胞核抗原（PCNA）及^3H-TdR及^3H-Leu掺入率在SHR-VSMC明显增强且呈剂量依赖关系；切除PDGF-α受体基因功能结构域后，PCDN及^3H-TdR及^3H-Leu掺入率显著降低。结论 SHR-VSMC中PDGF-A链及其α受体的自泌性增高，可能是导致SHR-VSMC异常生长，从而触发血管反应性和血管构型变化的重要原因之一，切除PDGF-α受体基因功能结构域将有效防止高血压平滑肌细胞的增殖和肥大。     

赖诺普利对自发性高血压大鼠血管平滑肌细胞离子泵活性及其mRNA表达的影响

目的 探讨赖诺普利对自发性高血压犬鼠动脉血管平滑肌细胞钠泵、钙泵活性及钠泵α1亚单位、钙泵亚型1mRNA表达水平的影响.方法 以自发性高血压大鼠动脉血管平滑肌细胞为研究对象,分为自发性高血压大鼠对照组、低剂量(1×10-6mol/L)赖诺普利组和高剂量(1×10-5mol/L)赖诺普利组,另以Wistar-Kyoto大鼠(WKY)为对照;分别用生化酶学方法和实时定量PCR检测细胞膜钠泵、钙泵活性和mRNA表达水平,用放射免疫分析法检测细胞培养液血管紧张素Ⅱ的含量.结果 与WKY对照组比较,自发性高血压大鼠动脉血管平滑肌细胞膜钠泵、钙泵活性及钠泵α1亚单位、钙泵亚型1mRNA表达水平均降低(P<0.01).赖诺普利能提高自发性高血压大鼠动脉血管平滑肌细胞膜钠泵、钙泵活性,并能上调钠泵α1亚单位和钙泵亚型1mRNA的表达水平(P<0.01).自发性高血压大鼠动脉血管平滑肌细胞培养液中血管紧张素Ⅱ含量高于WKY对照组(P<0.05),赖诺普利能降低其培养液中血管紧张素Ⅱ含量(P<0.05).结论 高血压大鼠动脉血管平滑肌细胞两种离子泵活性降低可能缘于它自身基因表达水平的下降,赖诺普利通过阻断血管紧张素Ⅱ而上调两种离子泵活性及基因表达.     

依那普利对自发性高血压大鼠平滑肌细胞Gqα基因表达的影响

目的:(1)自发性高血压大鼠是否存在Gqα基因表达的异常;(2)ACEI抑制血管平滑肌的增殖是否与抑制Gqα基因表达有关.方法:采用半定量RT-PCR方法,观察SHR及WKY主动脉血管平滑肌细胞静止期及增殖期Gqα基因表达情况以及依那普利对Gqα基因表达的影响.结果:(1)静止期,SHR及WKY血管平滑肌细胞Gqα mRNA表达无明显差别;在10%小牛血清刺激下,SHR血管平滑肌细胞Gqα mRNA表达增加四倍(P<0.01);(2)依那普利对静止期SHR Gqα mRNA表达无明显作用,对小牛血清引起的Gqα mRNA表达的增加有明显抑制作用,且呈浓度及时间依赖性;(3)非特异性肽类AngⅡ受体阻制剂无此作用.结论:SHR的Gqα基因表达反应性增加,依那普利对高血压病的治疗除抑制ACE 外,通过对Gq蛋白基因表达的抑制也起一定的作用.     

中药调控高血压血管平滑肌细胞增殖的研究进展

血管平滑肌细胞作为血管中膜的主要成分,其异常增殖是高血压血管重构以及血管增殖性疾病的主要病理基础。中药治疗高血压的临床效果肯定,目前对中药治疗高血压的机制等相关研究越来越深入。本文就近年来中药调控高血压血管平滑肌细胞增殖的研究进展做一综述。     

自发性高血压大鼠高血压形成前期血管平滑肌细胞增殖和肾…

通过体外培养３周龄自发性高血压大鼠（ＳＨＲ）胸主动脉血管平滑肌细胞（ＡＳＭＣ），探讨ＳＨＲ高血压形成前期ＡＳＭＣ是否存在异常增殖，以及与循环、血管局部血和紧张素Ⅱ（ＡｎｇⅡ、血管紧张素转换酶（ＡＣＥ）的关系。结果表明：３周龄ＳＨＲＡＳＭＣ肾素－血管紧张素系统（ＲＡＳ）处于高功能状态，合成ＡｎｇⅡ，ＡＣＥ，分泌ＡｎｇⅡ的量比ＷＫＹ高（Ｐ〈０．０５），并呈现异常增殖，３Ｈ－ＴｄＲ参入增加，倍增时间（Ｄ     

红细胞抗高血压因子对自发性高血压大鼠血管平滑肌细胞游离钙浓度的影响

观察从人红细胞中提取的抗高血压因子（ＡＨＦ）对自发性高血压大鼠（ＳＨＲ）和正常血压ＷＫＹ大鼠培养的主动脉平滑肌细胞胞内游离Ｃａ２＋浓度（［Ｃａ２＋］ｉ）的影响。结果ＳＨＲ和ＷＫＹ大鼠静息［Ｃａ２＋］ｉ无显著差别。ＫＣｌ（６０ｍｍｏｌ／Ｌ）对ＳＨＲ的激活显著大于ＷＫＹ大鼠，ＡＨＦ（１０－４ｇ／ｍｌ）可明显抑制由高钾诱导的［Ｃａ２＋］ｉ升高，对ＳＨＲ的抑制程度明显高于ＷＫＹ大鼠；去甲肾上腺素（ＮＥ，０．１ｍｍｏｌ／Ｌ）对两种大鼠的激活程度无显著差异。ＡＨＦ（１０－４ｇ／ｍＬ）也可明显抑制由ＮＥ（０．１ｍｍｏｌ／Ｌ）所诱导的ＶＳＭＣ［Ｃａ２＋］ｉ升高，对两种大鼠的抑制程度无显著差异。结论ＡＨＦ的降压作用可能与抑制细胞内［Ｃａ２＋］ｉ升高有关。     

大蒜素对自发性高血压大鼠肠系膜动脉平滑肌细胞钙电流的作用

目的:观察大蒜素(Gar)对自发性高血压大鼠(SHR)肠系膜动脉平滑肌细胞L-型钙电流(LCa,L)的影响。方法:利用双酶-两步法消化得到单个大鼠肠系膜动脉血管平滑肌细胞,用全细胞膜片钳记录钙电流。在细胞池中灌流含Gar的细胞外液,观察药物对LCa,L的作用和门控机制及门控动力学参数的改变。结果:1Gar对ICa,L的抑制效应呈浓度依赖性和电压依赖性特征。刺激电位0 mV时,200μmol/L Gar可使ICa,L峰值密度由(-8.4±0.4)pA/pF降低为(-6.1±0.3)pA/pF;2药物可使ICa,L半激活电压V1/2右移,半失活电压左移及失活后恢复动力学减慢等环节可减少通道的开放和重复开放,从而减少ICa,L峰值密度和窗口电流。结论:Gar可能通过减少细胞的钙电流发挥降压效应。     

自发性高血压大鼠高血压形成前期血管平滑肌细胞增殖和肾素-血管紧张素系统的关系

通过体外培养３周龄自发性高血压大鼠（ＳＨＲ）胸主动脉血管平滑肌细胞（ＡＳＭＣ），探讨ＳＨＲ高血压形成前期ＡＳＭＣ是否存在异常增殖，以及与循环、血管局部血管紧张素Ⅱ（ＡｎｇⅡ）、血管紧张素转换酶（ＡＣＥ）的关系。结果表明：３周龄ＳＨＲＡＳＭＣ肾素－血管紧张素系统（ＲＡＳ）处于高功能状态，合成ＡｎｇⅡ、ＡＣＥ，分泌ＡｎｇⅡ的量比ＷＫＹ高（Ｐ＜０．０５），并呈现异常增殖，３Ｈ－ＴｄＲ参入增加，倍增时间（ＤＴ）缩短（Ｐ＜０．０１）。血管紧张素转换酶抑制剂（ＡＣＥＩ）卡托普利、ＡｎｇⅡ受体拮抗剂Ｓａｒａｌａｓｉｎ长期干预可通过抑制ＳＨＲＡＳＭＣＡｎｇⅡ生成或阻断ＡｎｇⅡ的作用进而抑制其异常增殖。而ＷＫＹ血浆ＡｎｇⅡ、ＡＣＥ活性反比ＳＨＲ高（Ｐ＜０．０１）。说明：血管局部ＲＡＳ处于高功能状态对ＳＨＲ高血压前期ＡＳＭＣ异常增殖起重要作用，而循环ＲＡＳ则不起作用。     

氟伐他汀对高血压血管平滑肌细胞增殖的影响

目的:探讨氟伐他汀对自发性高血压大鼠血管平滑肌细胞增殖的抑制作用.方法:培养自发性高血压大鼠主动脉血管平滑肌细胞,不同浓度的氟伐他汀和甲羟戊酸干预后,进行细胞计数和3H-TdR掺入率的测定.结果:(1)氟伐他汀呈浓度依赖性(10-5～10-7mol)抑制血管平滑肌细胞数目的增加和3H-TdR的掺入率;(2)10-3mol的甲羟戊酸几乎完全逆转了氟伐他汀对血管平滑肌细胞增殖的抑制作用.结论:氟伐他汀抑制了高血压大鼠血管平滑肌细胞的增殖;甲羟戊酸代谢途径可能参与了血管平滑肌细胞的增殖过程.     

Cicletanine avoids the proliferation of vascular smooth muscle in the spontaneously hypertensive rat

The vasodilator and antiproliferative effects of the antihypertensive agent, cicletanine, were studied on mesenteric arteries (MA) and cultured mesenteric artery myocytes derived from spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats. Cicletanine induces relaxation of precontracted MA with an 1050 value of approximately 30-50 microM. Cicletanine inhibits the proliferation of cultured myocytes (passage 5) with an 1050 of 440 +/- 24 microM for SHR and 517 +/- 12 microM for WKY, p less than 0.05, indicating that a log-unit shift in sensitivity exists between its vasodilator and antiproliferative actions. Preliminary experiments suggest that the antiproliferative action of cicletanine is accompanied by an inhibition of DNA synthesis [( 3H] - thymidine uptake) in myocytes of SHR and a stimulation of DNA synthesis in myocytes of the WKY. Cicletanine also lowers free intracellular Ca2+ (determined using fura-2) in myocytes of SHR but not the WKY. In other cell systems, cicletanine has been shown to stimulate prostacyclin production. However, in the present experiments, inhibition of the cyclooxygenase pathway (5 microM indomethacin) attenuated the antiproliferative action of cicletanine by only 30% in cells of the SHR and was without affect in the WKY. In summary, we have shown that cicletanine has distinct antiproliferative effects cultured vascular myocytes. In SHR myocytes, the antiproliferative action is accompanied by a fall in intracellular Ca2+, stimulation of the cyclooxygenase pathway and an inhibition of DNA synthesis. Different mechanisms may be operant in cells of the WKY. It is proposed that the antiproliferative effects of cicletanine may play a role its antihypertensive actions.     

氟伐他汀对高血压血管平滑肌细胞增殖的影响

目的：探讨氟伐他汀对自发性高血压大鼠血管平滑肌细胞增殖的抑制作用。方法：培养自发性高血压大鼠主动脉血管平滑肌细胞,不同浓度的氟伐他汀和甲羟戊干预后,进行细胞计数和＾３Ｈ－ＴｄＲ掺入率的测定。结果：（１）氟伐他汀呈浓度依赖性（１０＾－５￣１０＾－７ｍｏｌ）抑制血管平滑肌细胞数目的增加和＾３Ｈ－ＴｄＲ的掺入率;（２）１０＾－３ｍｏｌ的甲羟戊酸几科完全逆转了氟伐他汀对血管平滑肌细胞增殖的抑制作用。结论：     

Differential effects of antihypertensive agents on proliferation of vascular smooth muscle cells from spontaneously hypertensive rats.

We have previously shown that Ca-antagonists and alpha-blockers substantially inhibit the cellular proliferation of cultured rat vascular smooth muscle cells (VSMC). This study explored whether these inhibitory effects on cellular proliferation differ between cultured VSMC from spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). SHR VSMC proliferated much faster than WKY VSMC in 10% FCS. Cellular proliferation, determined by both cell number count and 3H-thymidine incorporation, was significantly blunted in the presence of either nifedipine (Nif) or bunazosin (Bun). The magnitude of these inhibitory effects was more pronounced for SHR cells than WKY cells (% reduction of 3H-thymidine uptake with Nif: 62.1 +/- 7.8% for SHR vs 75.3 +/- 10.2% for WKY, n = 6, p less than 0.05, and with Bun: 70.2 +/- 7.8% for SHR vs 82.1 +/- 9.9% for WKY, n = 6, p less than 0.05). In contrast, the intracellular water volume was unaffected by these antihypertensive agents based on equilibrium distribution of 3-O-methyl-D-glucose14C. It is concluded that SHR VSMC grow much faster than WKY VSMC and that this abnormality is innate to the SHR cells. It is also concluded that both Ca-antagonists and alpha-blockers exerted a substantial inhibitory effect on cellular proliferation of the cultured VSMC of either SHR or WKY. Furthermore, the greater inhibition of proliferation in the SHR VSMC suggests that Ca mediated- and/or alpha-receptor mediated processes of cellular proliferation of SHR could differ from that of WKY and that these abnormalities may contribute to the hyperproliferative changes of VSMC in this model.     

瘦素通过其受体刺激小鼠血管平滑肌细胞增殖而促进动脉内膜增生

目的 探讨瘦素是否影响动脉内膜的增生及其发生机制.方法 利用野生型(Wt)、瘦素基因缺陷(Lep-/-)、瘦素受体基冈缺陷(LepR-/-)小鼠,通过股动脉内膜损伤及瘦素疗法,结合组织学特性,分析瘦素影响动脉内膜增生情况及其机制.结果 动脉内膜损伤后4周,Lep-/-和LepR-/-小鼠的内膜面积与中层面积比值(I/M)均小于Wt小鼠,差异均有统计学意义(Lep-/-小鼠比Wt小鼠为0.80±0.14比1.50±0.22,P<0.01;LepR-/-小鼠比Wt小鼠为0.55±0.20比1.50 ±0.22,P<0.05).Lep-/-和LepR-/-小鼠经动脉内膜损伤并同时给予瘦素治疗后,前者的I/M显著增加,而后者的I/M无明显变化.α-肌动蛋白和5-溴-2-脱氧尿嘧啶染色显示,二者在各组动脉增生内膜的阳性率分布趋势与内膜增厚程度一致.结论 瘦素缺乏或瘦素受体缺乏防止动脉内膜增生,外源性瘦素恢复Lep-/-小鼠动脉内膜增生,但对LepR-/-小鼠内膜无影响.本研究从动物模型上证明,高瘦素血症是动脉内膜增生的高危因素,并说明瘦素通过瘦素受体刺激血管平滑肌细胞增殖而促进动脉内膜增生.     

Coculture of vascular endothelial cells and smooth muscle cells from spontaneously hypertensive rats

The effect of endothelium-released vasoactive factors on vascular smooth muscle cell (VSMC) proliferation was studied in a coculture system. Isolated aortic endothelial cells and smooth muscle cells from 4-week-old spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) rats were cocultured. After coculture, the VSMC proliferation rate was examined by 3H-thymidine incorporation assay and the levels of the vasoactive factors in medium were determined by enzyme immunoassay (EIA). The results indicate that the proliferation rate of VSMCs in SHR was significantly higher than in WKY rats when VSMCs were cultured alone. When SHR vascular endothelial cells (VECs) were cocultured with VSMCs, the proliferation rate of SHR VSMCs was enhanced; however, there was no growth promoting effect in WKY VSMCs. When WKY VECs were cocultured with VSMCs, no VSMC proliferation effect was observed. When VSMCs were cultured alone, the endothelin-1 (ET-1) secretion in SHR was significantly higher than in WKY rats. When VECs and VSMCs were cocultured, the ET-1 concentration increased in both SHR VEC and WKY VEC coculture groups in a similar manner; but the SHR VECs tended to release more thromboxaneA2 (TXA2) and less PGI2 than WKY VECs. These results suggest that some kind of interaction between SHR VSMCs and SHR VECs is responsible for the high proliferation of SHR VSMCs but not the effects of SHR VECs per se.     

Autocrine effects of endothelin on in vitro proliferation of vascular smooth muscle cells from spontaneously hypertensive and normotensive rats

According to previous studies, endothelin-1 (ET-1) is the most potent growth factor in the regulation of vascular smooth muscle cell (VSMC) proliferation in spontaneously hypertensive rats (SHR). To evaluate if the dominant effect of ET-1-induced VSMC proliferation is achieved by autocrine regulation, aortic smooth muscle cells from four-week-old SHR and WKY (Wistar-Kyoto) rats were cultured in 24-well dishes, and the effects of ET-1 on VSMC proliferation were determined by (a) 3H-thymidine incorporation assays with different ET-1 blocking treatments, including a specific anti-ET-1 antibody; BQ-123, an ETA receptor blocker; and BQ-788, an ETB receptor blocker; and (b) examining the ET-1 blockade on the effects of treatment with other growth factors, including thrombin and angiotension II (AT-II). These results demonstrated that the anti-ET-1 antibody, BQ-123, BQ-788, and BQ-123 plus BQ-788 all caused dose-dependent inhibition of proliferation. A 90% inhibitory effect was observed at the maximum doses used except for BQ-123. The ET-1 receptor blockers inhibited thrombin-induced VSMC growth; however, they did not efficiently inhibit AT-II-induced VSMC growth. These results indicate that the autocrine effects of ET-1 play a predominant role in the proliferation of VSMCs from SHR and WKY rats. They also suggest that thrombin-induced VSMC growth is mediated by the autocrine effects of ET-1, and angiotensin II-induced VSMC growth is mediated by other signal pathways.     

莲心碱对自发性高血压大鼠血管平滑肌细胞增殖及对PDGF-B、bFGF、c-sis、c-myc的影响

用[~3H]胸腺嘧定核苷([~3H]TdR)掺入法、电镜、免疫组化和原位杂交方法,在自发性高血压大鼠(SHR)观察了莲心碱(Lien)对血管平滑肌细胞(VSMC)增殖的作用及对生长因子PDGFB、bFGF及其相关癌基因c-sis和c-myc表达的影响.结果发现Lien在降低SHR血压同时,能减少VSMC的线粒体,粗面内质网和[~3H]TdR掺入量,并能逆转VSMC增殖时PDGF-B、bFGF抗原及c-sis和c-myc mRNA的表达增强.提示Lien能抑制SHR的VSMC增殖,与生长因子及癌基因调控的分子生物学机制有关.     

Increased expression of osteoprotegerin in vascular smooth muscle cells from spontaneously hypertensive rats

Osteoprotegerin (OPG) is a secreted protein of the tumor necrosis factor receptor family,whichregulates bone mass by inhibiting osteoclast differentiation and activation.Although OPG is expressed ubiquitouslyand abundantly in many tissues and cell types including vascular cells,the role of OPG in other tissues is unknown.Our previous studies demonstrated that OPG was highly expressed in vascular smooth muscle cells (VSMC) andupregulated during vascular lesion formation.Methods and Results We documented,by Northern blot analysis,that the expression of OPG was more prevalent in the aorta and cultured VSMC from spontaneously hypertensive rats(SHR) compared to Wistar-Kyoto rats (WKY).In addition,we found that the expression of Angiotensin Ⅱ (Ang Ⅱ)type Ⅰ receptor (AT1R) in SHR VSMC was at significantly increased levels than in WKY VSMC.Furthermore,AngⅡ potently induced the expression of OPG in VSMC in a time- and dose-dependent manner through the AT1Rsignaling pathway.Conclusions OPG expression was substantially greater in SHR VSMC,suggesting that OPGmay be an important determinant of vascular remodeling in SHR.(J Ceriatr Cardiol 2004;1:49-54.)     

Isolation and characterization of single vascular smooth muscle cells from spontaneously hypertensive rats

To study the properties of vascular smooth muscle in hypertension without the influence of the nerves and endothelium, a procedure was developed to isolate single smooth muscle cells from tail arteries of spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) normotensive control rats. Perfusion of intact arteries with a solution of papain and collagenase produced dense populations of viable cells (more than 10(4) cells/ml) that remained relaxed in the presence of physiological levels of calcium. Contractile responses of smooth muscle cells from the SHR were significantly more sensitive to noradrenaline, potassium depolarization, and the calcium channel agonist Bay K 8644 compared with those from WKY rats. Enhanced sensitivity to calcium in the SHR was also observed on readdition of calcium to cells preincubated in noradrenaline or KCl in a calcium-free medium. These results provide evidence for alterations in the properties of vascular smooth muscle in the SHR at the single cell level.