贝那普利对百草枯中毒大鼠肺纤维化的干预作用

目的观察贝那普利对百草枯中毒大鼠肺纤维化过程的影响并探讨其可能的作用机制。方法72只SPF级SD雄性大鼠按随机数字表法分为对照组、百草枯染毒组（一次性百草枯60mg／kg灌胃）和贝那普利干预组[一次性百草枯60mg／kg灌胃并予贝那普利10mg／（kg·d）灌胃],每组24只。对照组用0．9％氯化钠注射液替代百草枯及贝那普利。各组于实验第3、7、14天分批随机处死8只动物,取肺组织行苏木素一伊红（HE）染色和Masson染色,观察大鼠肺泡炎、肺纤维化程度;免疫组织化学测胶原I、Ⅲ;定时定量聚合酶链反应检测血管紧张素转化酶（ACE）、血管紧张素Ⅱ1型受体（ATl）mRNA表达;酶联免疫吸附法检测肺组织血管紧张素Ⅱ（AngⅡ）蛋白表达。结果百草枯染毒组第3、7、14天大鼠肺组织ACEmRNA、AT1 mRNA及AngⅡ蛋白表达均较对照组增高[ACEmRNA分别为（3．15±0．13）比（1．02±0．01）、（3．88±0．21）比（1．05±0．02）、（4．16±0．12）比（1．03±0．01）,AT1 mRNA分别为（1．53±0．23）比（1．00±0．01）、（2．92±0．05）比（1．06±0．03）、（3．62±0．03）比（1．08±0．05）,Angll分另0为（10．55±0．24）μg／L比（3．00±0．12）斗g／L、（7．43±0．23）彬L比（3．05±0．16）彬L、（8．36±0．35）形L比（3．03±0．13）μg／L];贝习B普利干预组[第3、7、14天ACEmRNA分别为（2．20±0．22）、（2．95±0．08）、（2．80-t-O．16）,ATlmRNA分别为（1．32±0．01）、（2．05±0．17）、（2．53±0．22）,Angll分别为（5．85±0．32）、（6．21±0．16）、（6．13±0．33）μg／L]与百草枯染毒组比,表达下调（P〈0．05）。贝那普利干预组第7天始肺泡炎和纤维化程度积分及胶原I、Ⅲ含量低于百草枯染毒组（P〈0．05）。结论局部。肾素-血管紧张素系统的激活可能参与百草枯中毒致肺纤维化的发病过程。贝那普利对百草枯中毒大鼠肺纤维化有一定阻抑作用,可能与其抑制局部ACE,减少AngⅡ生成有关。     

阻断肾素-血管紧张素-醛固酮系统不同位点对百草枯中毒大鼠肺纤维化的影响

目的 观察通过药物阻断肾素-血管紧张素-醛固酮系统的不同位点对百草桔中毒大鼠肺纤维化的影响及探讨可能的作用机制.方法 SD大鼠一次性百草枯80mg/kg灌胃建立肺纤维化模型,分别每日胃管内灌注生理盐水(染毒组)、卡托普利60 mg/kg、氯沙坦10mg/kg和螺内酯100 mg/kg进行干预.对照组以生理盐水灌胃.各组大鼠均于染毒后第7、14、28 d分批处死,取肺组织行苏木素-伊红(HE)与Masson染色并行肺泡炎、肺纤维化评分,测肺羟脯氨酸(Hyp)含量,用免疫组化法和图像半定量分析系统检测肺组织结缔组织生长因子(CTGF)蛋白的表达.结果 各干预组各时间点大鼠肺泡炎和肺纤维化程度积分、肺Hyp含量、肺组织CTGF蛋白的表达均低于染毒组(P＜0.01).3组采用药物干预后,肺Hyp含量比较的差异有统计学意义(P＜0.05).结论 卡托普利、氯沙坦与螺内酯均能减轻百草枯中毒大鼠肺纤维化的程度,可能通过阻断不同的受体抑制CTGF蛋白的表达而实现.螺内酯减轻肺组织胶原沉积的疗效最佳,氯沙坦最差.     

螺内酯阻抑百草枯中毒大鼠肺纤维化的机制探讨

目的观察螺内酯能否阻抑百草枯（PQ）中毒大鼠肺纤维化及探讨其可能的作用机制。方法54只雄性SD大鼠随机分为对照组、PQ染毒组（一次性PQ80mg／kg灌胃）和螺内酯干预组（一次性PQ80mg／kg灌胃并予每天1次螺内酯100mg／kg灌胃）。各组大鼠于染毒后第7、14、28天分批处死,取肺组织行HE染色、Masson染色并做肺泡炎、肺纤维化评分,计算肺系数,测血浆及肺组织醛固酮（ALD）含量及肺羟脯氨酸含量,应用免疫组化法测肺组织转化生长因子-β1（TGF-β1）及α-平滑肌肌动蛋白（α—SMA）蛋白的表达。结果染毒组和干预组血浆、肺组织ALD含量均较对照组升高,第14天始差异有统计学意义（P〈0．05）;干预组各时间点大鼠肺泡炎和肺纤维化程度积分、肺系数、肺羟脯氨酸含量均低于染毒组（P〈0．01）;干预组第14天始肺组织TGF—β1、α-SMA蛋白的表达均低于染毒组（P〈0．05或P〈0．01）。结论ALD、TGFβ1、α—SMA可能均参与PQ中毒致肺纤维化的发病进程。螺内酯对PQ中毒大鼠肺纤维化有一定程度的阻抑作用,可能与其抑制ALD受体,并减少肺部TGF-β1和aSMA的表达有关。     

百草枯中毒致大鼠肺纤维化模型中肺组织的PAI-1mRNA表达

目的 观察纤溶酶原激活物抑制因子-1(PAI-1)在百草枯致大鼠肺纤维化模型中肺组织的表达情况.方法 42只健康成年雌性SD大鼠随机分为对照组和染毒组,分别观察7、14和28 d.染毒组于实验开始一次性百革枯(40mg/kg)灌胃染毒,对照组予以等量生理盐水.取肺组织行病理组织学检查,并采用RT-PCR法测定PAI-1 mRNA的表达.结果 百草枯染毒后大鼠肺泡炎、肺纤维化程度积分明显增高;肺组织PAI-1 mRNA表达(7、14、28 d分别为1.30±0.37,2.39±0.17、0.56±0.05)明显高于同期对照组(0.07±0.02),差异有统计学意义(P<0.01).结论 百草枯中毒大鼠肺组织PAI-1 mRNA水平的表达明显上调.     

红景天苷对百草枯中毒大鼠肺组织TGF-β1表达的影响

【】 目的 研究红景天苷(SDS)对百草枯(PQ)中毒大鼠肺组织TGF-β1表达的影响。方法 将130只SD大鼠随机分为正常对照组、PQ模型组、SDS治疗组,后两组又分为1天、3天、7天、14天、21、28天6个亚组,每亚组10只。PQ模型组和SDS治疗组采用一次性灌胃百草枯溶液(20mg/Kg)的方法,制备急性PQ中毒肺损伤模型,染毒1小时后分别给予相同体积的生理盐水、SDS(10mg/Kg)腹腔注射。各组在相应时间点取材,采用免疫组化、RT-PCR测定肺组织中转化生长因子β1(TGF-β1)及其mRNA的表达情况。结果 免疫组化结果显示,与正常对照组比较,PQ模型组、SDS治疗组肺组织TGF-β1表达显著增加(P<0.05),在第14天达到最大值。与PQ模型组各时间点比较,SDS干预组中TGF-β1的表达量低,两者差异有统计学意义(P<0.05)。RT-PCR结果显示模型组与SDS干预组染毒后第1天大鼠肺组织TGF-β1mRNA水平开始增加,在第14天达到最高值,第28天基因表达恢复正常。SDS治疗组TGF-β1mRNA表达量比模型组低,二者比较有统计学差异(P<0.05)。结论 TGF-β1参与了PQ中毒大鼠肺纤维化病理生理过程,SDS能抑制TGF-β1的表达,减轻PQ中毒大鼠肺损伤。     

百草枯中毒急性肺损伤的作用机制及丙酮酸乙酯干预研究

目的 探讨高迁移组蛋白B1(HMGB1)/Toll样受体4(TLR-4)在百草枯(PQ)中毒导致急性肺损伤作用机制及丙酮酸乙酯(EP)干预研究.方法 将90只SD大鼠均分为对照组、百草枯中毒组、丙酮酸乙酯治疗组,建立大鼠急性百草枯中毒动物模型后,分别于实验后的6、12、24、48 h、3 d每组随机处死6只大鼠,检测三组大鼠肺组织中肿瘤坏死因子-α(TNF-α)、HMGB1、白细胞介素-1(IL-1)和TLR-4mRNA变化;并测定三组大鼠血清中丙二醛(MDA)、超氧化物歧化酶(SOD)活性变化.结果 与对照组相比,PQ中毒组和EP治疗组染毒后6、12、24、48 h、3 d各时间点,肺组织TNF-α mRNA、HMGB1 mRNA、IL-1 mRNA、TLR-4 mRNA的表达量和丙二醛含量明显升高(均P<0.05),SOD 活力降低(均P<0.05);与PQ中毒组相比,EP治疗组在染毒后12、48 h时间点大鼠肺组织HMGB1 mRNA、TLR-4 mRNA、IL-1 mRNA、TNF-α mRNA表达量及血清MDA含量均降低(均P<0.05),血清SOD 活力均升高(均P<0.05).结论 百草枯中毒急性肺损伤的机制主要与氧化应激、细胞膜脂质过氧化及免疫系统炎症级联放大效应有关,丙酮酸乙酯可通过抑制该过程从而减轻急性肺损伤程度.     

ACE2对大鼠心肌梗死后心肌重构的影响

目的探讨大鼠心肌梗死（MI）后心肌组织中AngⅡ的表达与心肌重构的关系,进一步阐明ACE2对大鼠MI后心肌重构的作用机制。方法将32只健康雄性SD大鼠随机分为假手术组（n=8）、MI组（n=8）、氯沙坦小剂量组[MI＋10 mg/（kg·d）,n=8]和大剂量组[MI＋20 mg/（kg·d）,n=8],随后将MI组和氯沙坦组大鼠建立心尖部心梗模型。术中检测梗死前后心电图变化情况。术后4周取大鼠心尖部心肌组织,HE染色观察心肌组织病理改变情况,RT-PCR检测心肌内AngⅡ和ACE2的mRNA表达量。结果 HE染色结果显示,MI组与假手术组相比,大鼠心肌细胞肿胀、变形、破裂增多,MI组心肌内AngⅡ的mRNA表达量显著高于假手术组,给予氯沙坦后,表达量呈剂量依赖性下降。MI组心肌内AngⅡ的mRNA表达量显著高于假手术组,给予氯沙坦后,表达量呈剂量依赖性下降。MI组心肌内ACE2的mRNA表达量略高于假手术组,氯沙坦组继续升高,呈剂量依赖性。结论氯沙坦组大鼠ACE2表达量增加,进而通过抑制心肌组织内AngⅡ表达来改善MI后的心室重构。     

早期百草枯中毒大鼠肺和肝组织NF—κBp65、MCP-1mRNA表达的变化

目的探讨百草枯（PQ）中毒的分子机制。方法应用半定量RT-PCR法检测PQ中毒大鼠染毒4h后肺、肝组织核因子-κBp65（NF-κBp65）、单核细胞趋化蛋白-1（MCP-1）mRNA的表达,并与正常对照组比较。结果大鼠PQ染毒4h后,肺、肝组织NF-κBp65、MCP-1mRNA的表达明显上调,与对照组相比差异有统计学意义（P〈0．01）。结论PQ中毒大鼠4h内肺、肝组织NF—κBp65、MCP-1mRNA表达就已明显上调,提示在PQ致机体中毒的毒性过程中,早期就有细胞因子的参与。     

氯沙坦对百草枯急性染毒大鼠肺组织细胞因子水平的影响

目的观察百草枯急性染毒大鼠肺组织细胞因子水平的变化,探讨氯沙坦对大鼠百草枯急性肺损伤的干预作用。方法选择成年SD大鼠32只,随机分为对照组(NS组)、百草枯(PQ)组以及氯沙坦干预7和14 d组。NS组每天灌胃生理盐水;PQ组为PQ 40 mg/kg一次性灌胃染毒,此后每天灌胃生理盐水;氯沙坦干预组为PQ 40 mg/kg一次性灌胃染毒后,氯沙坦10 mg/kg·d连续灌胃给药7和14 d。各组分别于第15d处死并取肺组织,常规制备肺组织病理切片,苏木素-伊红(HE)染色后光学显微镜观察肺组织病理学改变。制备组织匀浆并离心取上清液,采用酶联免疫吸附法(ELISA)测定大鼠肺组织中IFN-γ、TNF-α、IL-8、IL-10的含量。结果 (1)病理检查结果显示,PQ急性染毒后大鼠肺泡间隔弥漫性显著增宽,部分区域可见炎性细胞浸润,间质小血管壁增厚,经氯沙坦干预后病理改变有一定程度的逆转。(2)与NS组比较,PQ染毒后大鼠肺组织中IL-8和TNF-α含量升高(P0.05),而IL-10和IFN-γ的含量明显降低(P0.05)。与PQ组比较,氯沙坦干预7和14 d组IL-8、TNF-α、IL-10和INF-γ含量均逐渐升高(P0.05);与NS组比较,氯沙坦干预7和14 d组IL-10和INF-γ含量基本恢复正常(P0.05)。结论炎症因子可能参与PQ急性肺损伤过程,且氯沙坦对PQ引起的肺组织炎性因子异常改变具有一定的逆转作用。     

苯那普利与厄贝沙坦对心衰大鼠心室重构过程中AngⅡ受体及ACE2的影响

目的探讨苯那普利、厄贝沙坦及两者联合用药对心衰大鼠心室重构过程中心肌血管紧张素Ⅱ1型受体(AT1R)、2型受体(AT2R)及ACE2蛋白表达的影响。方法采用大鼠腹主动脉缩窄法造成压力负荷性心肌肥厚致心力衰竭模型。苯那普利或(和)厄贝沙坦连续给药8wk,检测血流动力学参数、心脏指数、心肌和血浆AngⅡ含量、心肌中AT1R、AT2R和ACE2蛋白的表达情况。结果模型组心脏指数、LVEDP、血浆和心肌AngⅡ的含量及心肌AT1R、AT2R和ACE2蛋白的表达明显升高;各治疗组心脏指数、LVEDP明显下降;苯那普利组血浆和心肌AngⅡ的含量降低,厄贝沙坦组心肌AT1R蛋白的表达明显下降而AT2R和ACE2蛋白的表达明显升高,联合应用具有协同作用。结论联合应用苯那普利和厄贝沙坦对改善心衰大鼠心室重构具有协同作用,可能与AngⅡ和AT1R的下调而AT2R和ACE2的上调有关。     

ACE inhibitors and proteinuria

This review discusses the clinical consequences of uninary protein loss and the effects of inhibitors of the angiotensin converting enzyme (ACE) on this clinical finding. Proteinuria appears to be an important risk factor for renal function deterioration and for cardiovascular mortality. ACE inhibitors have been shown to reduce proteinuria more effectively than other antihypertensives. Their antiproteinuric effect seems to be independent of the underlying renal disease, and is mediated by a specific, not yet fully elucidated mechanism. Urinary protein loss related phenomena, such as hypoalbuminemia and aberrant lipoprotein profile, tend to improve also during ACE inhibitor treatment. Furthermore, ACE inhibition has been shown to prevent the renal function deterioration that is frequently observed in patients with renal disease. Interestingly, it has recently been shown that in proteinuric patients with renal disease the initial proteinuria lowering response to ACE inhibition predicts long-term renal function outcome during this treatment: the more proteinuria is lowered during the first months, the better renal function will be preserved over the following years. Because of these favorable effects ACE inhibitors have become a widely used class of agents in nephrology. They are not only prescribed for lowering blood pressure in the hypertensive renal patient, but also as symptomatic treatment of patients with proteinuria, and to prevent renal function loss in patients with both diabetic and non-diabetic renal disease.R.T. Gansevoort, D. de Zeeuw, P.E. de Jong, Ace inhibitors and proteinuria. Pharm World Sci 1996; 18(6): 204–210.     

Insertion/deletion polymorphism of the ACE gene and adherence to ACE inhibitors

AIMS: We investigated whether the insertion/deletion (I/D) polymorphism of the ACE gene modified the adherence to ACE inhibitors as measured by the discontinuation of an ACE inhibitor, or addition of another antihypertensive drug. METHODS: This was a cohort study among 239 subjects who started ACE inhibitor therapy. A Cox proportional hazard model was used to calculate relative risk (RR). RESULTS: During follow-up there was no significant difference between subjects with the DD, ID or II genotype (DD vs II; RR = 1.17, 95%CI: 0.78, 1.77 and ID vs II; RR = 1.06, 95%CI: 0.73, 1.55) in adherence. CONCLUSIONS: The I/D polymorphism of the ACE gene does not influence the adherence to ACE inhibitors.     

ACE inhibitors

Edited by P. D'Orlèans-Juste & G. E. Plante Published by Birkhauser [Milestones in drug therapy series] 187 pages, price @116, ISBN 3-7643-5982-X     

ACE基因多态性与ACE、血管紧张素Ⅱ及醛固酮的关系

目的:探讨原发性高血压患者血管紧张素转化酶(ACE)基因插入/缺失(I/d)多态性与血清ACE、血管紧张素Ⅱ及醛固酮的关系。方法:应用PCR技术测定146例高血压患者的ACE基因型,并测定其血清ACE、血管紧张素Ⅱ及醛固酮浓度。结果:ACE在DD、ID、Ⅱ三种ACE基因型之间的差异有显著性,ACE活性DD>IDⅡ,而血管紧张素Ⅱ及醛固酮在三种基因型之间的差异无显著性。结论:ACE基因多态性与ACE密切相关,而与血清血管紧张素Ⅱ及醛固酮没有关系。     

ACE2 and diabetic complications

Angiotensin converting enzyme (ACE) is a key enzyme in the renin angiotensin system (RAS) and converts angiotensin (Ang) I to the vasoconstrictor Ang II, which is thought to be responsible for most of the physiological and pathophysiological effects of the RAS. This classical view of the RAS was challenged with the discovery of the enzyme, ACE2 which both degrades Ang II and leads to formation of the vasodilatory and anti-proliferative peptide, Ang 1-7. Activation of the RAS is a major contributor to diabetic complications, and blockade of the vasoconstrictor and hypertrophic actions of Ang II, slows but does not prevent the progression of such complications. The identification of ACE2 in the heart and kidney adds further complexity to the RAS, provides the rationale to explore the role of this enzyme in pathophysiological states, including the microvascular and macrovascular complications of diabetes. It is believed that ACE2 acts in a counter-regulatory manner to ACE to modulate the balance between vasoconstrictors and vasodilators within the heart and kidney, and may thus play a significant role in the pathophysiology of cardiac and renal disease. Relatively little is known about ACE2 in diabetes, and this review will explore and discuss the data that is currently available. The discovery of ACE2 presents a novel opportunity to develop drugs that specifically influence ACE2 activity and/or expression, and it is possible that such compounds may have considerable clinical value in the prevention and treatment of the complications of diabetes.     

ACE基因多态性及其血浆水平与老年脑卒中的关系

目的 探讨老年脑卒中的发生与血管紧张素转换酶(ACE)基因插入/缺失多态性及其血浆ACE水平的关系.方法 应用多聚酶链反应(PCR)方法检测ACE基因多态性,同时用比色法测定血浆ACE水平.对89例老年脑卒中患者(缺血性脑卒中50例,出血性脑卒中39例)与51例老年健康对照者进行比较分析.结果 老年脑卒中组D等位基因频率显著高于对照组(0.58/0.36, P＜0.05),DD基因型患者血清ACE水平亦显著高于对照组[(42.38±16.61) U/L /(31.28±8.64) U/L, P＜0.05].而出血性脑卒中组与缺血性脑卒中组等位基因及血浆ACE水平无显著差异.结论 血浆ACE水平和ACE基因多态性有关,D等位基因是老年脑卒中的基因危险因素.     

ACE inhibitor-mediated angioedema

Angioedema (AE) occurring during ACE inhibitor therapy (ACEi-AE) is a rare complication involving between 0.1 and 0.7% of treated patients. AE can also complicate other therapeutic regimens that block the renin-angiotensin aldosterone system. Other drugs, such as immune suppressors, some type of antidiabetics or calcium antagonists, can increase the likelihood of ACEi-AE when associated to ACEi. There is a clear ethnic predisposition, since African-Americans or Hispanics show a higher prevalence of this condition compared to Caucasians. At least in African-Americans the genetic predisposition accounts for a general higher prevalence of AE, independently from the cause. People that experience ACEi-AE may have some recurrence when they are switched to an angiotensin-receptor blocker (ARB); however, epidemiological studies on large cohorts have shown that angiotensin receptor blockers (ARB) do not increase the likelihood of AE compared to other antihypertensives. Clinical manifestations consist of edema of face, lips, tongue, uvula and upper airways, requiring intubation or tracheotomy in severe cases. Attacks last for 48–72 h and require hospital admission in most cases. Intestinal involvement with sub-occlusive symptoms has also been reported.The pathogenesis of ACEi-AE depends mainly on a reduced catabolism and accumulation of bradykinin, which is normally metabolized by ACE. Genetic studies have shown that some single nucleotide polymorphisms at genes encoding relevant molecules for bradykinin metabolism and action may be involved in ACEi-AE, giving a basis for the ethnic predisposition. Treatment of ACEi-AE is still a matter of debate. Corticosteroids and antihistamines do not show efficacy. Some therapeutic attempts have shown some efficacy for fresh frozen plasma or C1 inhibitor concentrate infusion. Interventional studies with the specific bradykinin receptor antagonist icatibant have shown conflicting results; there might be a different ethnic predisposition to icatibant efficacy which has been proven in caucasian but not in black patients.     

ACE抑制肽的合成及其活性研究

为研究血管紧张素转换酶 (angiotensin converting enzyme, ACE) 抑制肽体外抑制ACE活性以期筛选出有降压作用的先导物, 采用Fmoc固相合成法合成ACE抑制肽, 经反相高效液相色谱法 (RP-HPLC) 分离纯化, 采用质谱对其进行鉴定, 并使用RP-HPLC法直接测定ACE抑制肽对ACE的体外抑制活性。合成的6个八肽经RP-HPLC纯化后, 质谱分析结果与理论值一致。活性评价结果表明6号八肽 (抗SARS肽) 对ACE的抑制作用最明显, 其IC₅₀为3.4×10⁻⁵ mol·L⁻¹, 由此可见抗SARS肽 (AVLQSGFR-OH) 是一个具有降压作用的先导物, 具有进一步研究的意义。