糖尿病酮症酸中毒并肝损害临床分析

目的探讨导致糖尿病酮症（ＤＫ）及酮症酸中毒（ＤＫＡ）患者肝损害的相关因素．方法ＤＫ或ＤＫＡ患者９９例,其中ＡＬＴ及ＡＳＴ均异常升高１１例（Ａ组）,单项ＡＬＴ异常升高１３例（Ｂ组）,肝功能正常７５例（Ｃ组）,对以上各组患者的血二氧化碳结合力（ＣＯ２ＣＰ）、尿素氮（ＢＵＮ）、血糖（ＢＧ）和血浆渗透压（ＯＳＭ）进行了统计分析．结果Ａ,Ｂ两组患者的ＣＯ２ＣＰ明显低于Ｃ组（Ｐ＜００１,ｔ＝６３３和ｔ＝６４３）,而ＢＵＮ则明显升高（Ｐ＜００１,ｔ＝３６１,ＡｖｓＣ;Ｐ＜００１,ｔ＝４３５,ＢｖｓＣ）,Ａ组的ＢＧ（Ｐ＜００５,ｔ＝２８４）和血浆ＯＳＭ（Ｐ＜００５,ｔ＝３１０）水平也显著高于Ｃ组,而Ｂ组患者的ＢＧ及血浆ＯＳＭ与Ｃ组比较无差异;与Ｂ组相比,Ａ组患者的ＣＯ２ＣＰ明显降低（Ｐ＜００２,ｔ＝２７１）,ＢＧ（Ｐ＜００５,ｔ＝２８９）和血浆ＯＳＭ（Ｐ＜００５,ｔ＝２３６）明显升高．此外,Ⅰ型糖尿病患者血清转氨酶异常升高的发生率明显高于Ⅱ型糖尿病患者（Ｐ＜００５,χ２＝４３８）．结论酸中毒和脱水是导致糖尿病酮症及酮症酸中毒患者肝损害的重要因素,酸中毒及脱水程度与肝损害程度相关．     

不同起搏方式对病窦综合征患者远期效果的影响

为了解不同起搏方式对病窦综合征特别是慢－快综合征患者心功能及房性心律失常的影响，利用超声心动图、体表心电图及Ｈｏｌｔｅｒ检查，对２１１例病窦综合征患者采用自身对照方法进行回顾性分析。结果发现：生理性起搏（ＡＡＩ／ＤＤＤ）组术后左室射血分数（ＬＶＥＦ）、心输出量（ＣＯ）明显增加（ＡＡＩ：５３．５±６．１％ｖｓ４７．２±７．８％，４．９５±０．５７Ｌ／ｍｉｎｖｓ４．２０±０．６２Ｌ／ｍｉｎ；ＤＤＤ：５２．５±６．８％ｖｓ４４．３±０．１％，５．１２±０．７１Ｌ／ｍｉｎｖｓ４．４１±０．３８Ｌ／ｍｉｎ；Ｐ均＜０．０１），左房内径（ＬＡＤ）无明显变化；ＤＤＤ组Ｅ／Ａ比值明显增加（０．９８±０．０９ｖｓ０．８７±０．１５，Ｐ＜０．０１），ＡＡＩ组Ｅ／Ａ比值呈增加趋势（Ｐ＝０．０５７）。房性心律失常发生率明显减少（１５．９％ｖｓ５０％，Ｐ＜０．０１）。非生理性起搏（ＶＶＩ）组术后ＬＶＥＦ、ＣＯ明显下降（４４．１±４．７％ｖｓ４８．３±４．３％，３．７７±０．４２Ｌ／ｍｉｎｖｓ４．１７±０．８５Ｌ／ｍｉｎ，Ｐ均＜０．０１），ＬＡＤ明显增大（３９．２６±２．３７ｍｍｖｓ３６．８１±２．３５ｍｍ，Ｐ＜０．０１），Ｅ／Ａ比值呈?     

经皮球囊二尖瓣成形术对心率变异的影响

为了解经皮球囊二尖瓣成形术（ＰＢＭＶ）对风湿性心脏病二尖瓣狭窄病人心率变异（ＨＲＶ）的影响，自同期行ＰＢＭＶ的７１例病人中选择窦性心律者作为观察对象。于术前二日和术后第三日记录５ｍｉｎ的心搏数，经短时ＨＲＶ软件分析。结果表明术后ＲＲ间期均值标准差（３３．１８±１０．４２ｍｓｖｓ４２．８０±１５．８４ｍｓ，Ｐ＜０．０５）、相邻ＲＲ间期差值的均方根（２９．６１±１３．３８ｍｓｖｓ３７．５２±２６．０８ｍｓ，Ｐ＜０．０５）、相邻ＲＲ间期差值大于５０ｍｓ的百分比（６．７６±７．４９％ｖｓ９．０３±１０．２３％，Ｐ＜０．０１）、高频能谱（６１５．５８±４８５．６２ｂｐｍ２ｖｓ７０１．９７±６４９．９６ｂｐｍ２，Ｐ＜０．０５）均明显增大或升高。而平均心率（７４．３２±１１．３７ｂｐｍｖｓ６５．８８±７．７３ｂｐｍ，Ｐ＜０．０１）、最大心率（９５．６８±２８．６８ｂｐｍｖｓ７６．１４±８．５３ｂｐｍ，Ｐ＜０．０１）、低频能谱（４３８．２２±４０９．３１ｂｐｍ２ｖｓ２４０．１８±１９８．６８ｂｐｍ２，Ｐ＜０．０１）、极低频能谱（９７１．７４±５２９．５３ｂｐｍ２ｖｓ７２１．４３±５６４．０９ｂｐｍ２，Ｐ＜０．０１）均明显降?     

腹主动脉结扎大鼠心房纤维化的实验研究

高血压患者有较高心律失常的发生率，房性心律失常可能与左房扩大或心房纤维化有关。为观察压力负荷增高大鼠中心房纤维化的发生情况，将Ｗｉｓｔａｒ大鼠随机分成假手术组和手术组，手术组大鼠行肾上腹主动脉部分结扎。术后４，８，１２周分别测定大鼠颈动脉压及心房胶原容积分数（ＣＶＦ），结果发现：①手术组左室舒张压明显高于假手术组（４，８，１２周分别为１８．５±２．５ｋＰａｖｓ１５．７±１．９ｋＰａ，１８．６±２．７ｋＰａｖｓ１５．３±１．３ｋＰａ，１９．６±３．１ｋＰａｖｓ１５．２±１．９ｋＰａ，Ｐ＜０．０５或０．０１）。②手术组心房ＣＶＦ明显高于假手术组（４，８，１２周左、右房分别比较：４．２３±０．７６％ｖｓ２．９３±０．８７％，４．６５±１．４５％ｖｓ３．１１±１．０７％，５．６２±１．６２％ｖｓ３．２３±１．２８％；３．８８±１．１５％ｖｓ２．５１±０．８４％，４．２４±１．６５％ｖｓ２．５１±０．８４％，５．３４±１．３２％ｖｓ２．３３±１．１４％；Ｐ＜０．０５或０．０１），手术组心房ＣＶＦ有逐渐上升趋势。③左房ＣＶＦ与左室舒张压之间无直线相关关系（ｒ＝０．１６９１，Ｐ＞０．０５）。提示在高血压大鼠模型中存在心房?     

风湿性心脏病心房颤动电生理机制的研究

报告２１例风湿性心脏病（简称风心病）慢性心房颤动（简称房颤）患者（ＣＡｆ组）的心外膜标测及心电生理结果，并与１４例非风心病阵发性房颤（ＰＡｆ组）和１２例无房颤者（正常对照组）进行对照，以对房颤机制进行研究进而为房颤外科术式的改良提供依据。ＣＡｆ组右房传导时间延长发生率（８０．０％）显著高于ＰＡｆ组（４２．９％）和正常对照组（８．３％），Ｐ＜０．０５和＜０．０００１。ＣＡｆ组和ＰＡｆ组窦性心律时的房间传导时间显著长于正常对照组（分别为１０３．０±２４．５和１１３．３±２６．１ｍｓｖｓ７８．７±１８．１ｍｓ，Ｐ均＜０．０１）。ＣＡｆ组和ＰＡｆ组的高位右房有效不应期均显著短于正常对照组（２２５．９±２２．２和２１０．０±３９．３ｍｓｖｓ２４８．８±３１．４ｍｓ，Ｐ＜０．００１和＜０．０１）。ＣＡｆ组和ＰＡｆ组易损性发生率（均为５０％）显著高于正常对照组（０），Ｐ均＜０．０１。ＣＡｆ组心外膜标测房颤时的波长指数显著小于房扑时的波长指数（１．４２±０．２７ｖｓ２．４２±０．４１，Ｐ＜０．０１）。右房多为细密的颤动波，左房多为规则的扑动波，但激动模式多变。表明右房传导时间延长、有效不应期短、易损性高是风心病ＣＡｆ的     

老年慢性阻塞性肺疾病患者血浆内皮素－1含量与PaO_2、PaCO_2及肺动脉压的关系

目的探讨血浆内皮素－１（ｅｎｄｏｔｈｅｌｉｎ－１，ＥＴ－１）在慢性阻塞性肺疾病（ｃｈｒｏｎｉｃｏｂｓｔｒｕｃｔｉｖｅｐｕｌｍｏｎａｒｙｄｉｓｅａｓｅ，ＣＯＰＤ）中的作用。方法应用放射免疫法测定４３例老年ＣＯＰＤ急性发作期患者和１５名健康对照者血浆ＥＴ－１水平，其中８例肺心病患者行右心微导管检测肺动脉压。结果ＣＯＰＤ患者和肺心病患者的血浆ＥＴ－１含量分别为５．２４±０．５０、５．８０±０．６６ｐｇ／ｍｌ，较健康对照组血浆ＥＴ－１含量（４．６５±０．６５ｐｇ／ｍｌ）明显升高（Ｐ值＜０．０１及０．００１）；血浆ＥＴ－１含量与ＰａＯ２呈显著性负相关（ＣＯＰＤ组：ｒ值＝－０．５８３，Ｐ值＜０．０１；肺心病组：ｒ值＝－０．６２７，Ｐ值＜０．００１），与ＰａＣＯ２呈显著性正相关（ＣＯＰＤ组：ｒ值＝－０．５１４，Ｐ值＜０．０５；肺心病组：ｒ值＝０．５９３，Ｐ值＜０．００１）；ＥＴ－１含量与肺动脉收缩压及平均压均存在正相关（ｒ值＝０．７２７及０．６８１，Ｐ值均＜０．０５）。结论血浆ＥＴ－１参与肺心病肺动脉高压的形成，缺氧和二氧化碳潴留是刺激ＥＴ－１释放的重要原因之一     

心肌缺血大鼠的心率功率谱变化及其与心脏性猝死关系的研究

采用心率变异（ＨＲＶ）频域指标定量评价心肌缺血大鼠的心脏自主神经功能变化及其与心脏性猝死（ＳＣＤ）的关系。Ｈｏｌｔｅｒ监测仪记录假手术组（２０只）及心肌缺血后存活组（５４只）与ＳＣＤ组（３６只）大鼠的心电信号。结果显示存活组或ＳＣＤ组大鼠于心肌缺血初始１５ｍｉｎ内的低频（ＬＦ）及低频／高频比值（ＬＦ／ＨＦ）较假手术组明显升高〔ＬＦ（ｍｓ２／Ｈｚ）：１９８．８±４１．３或２２６．７±５６．４ｖｓ６５．４±１９．６，Ｐ均＜０．０１；ＬＦ／ＨＦ：４．０８±１．１或５．１２±１．４ｖｓ１．８７±０．７，Ｐ均＜０．０１〕，而且ＳＣＤ组大鼠的ＬＦ与ＬＦ／ＨＦ较存活组增高〔ＬＦ（ｍｓ２／Ｈｚ）：２２６．７±５６．４ｖｓ１９８．８±４１．３，Ｐ均＜０．０５；ＬＦ／ＨＦ：５．１２±１．４ｖｓ４．０８±１．１，Ｐ＜０．０５〕，各组间ＨＦ无明显变化；ＳＣＤ组大鼠于ＳＣＤ发生前１５ｍｉｎ内，心率功率谱动态变化表现为ＬＦ及ＬＦ／ＨＦ随死亡时间的濒临而呈进行性升高（Ｐ＜０．０１及０．０５）。表明大鼠心肌缺血后其交感神经活性明显亢进，ＨＲＶ降低与ＳＣＤ的发生密切相关。     

双丁酰环腺苷酸对体外HT29细胞增殖的调节

采用酸性磷酸酶细胞原位计数及流式细胞仪（ＦＣＭ）技术，观察了双丁酰环腺苷酸（ｄｂ－ｃＡＭＰ）对体外人结肠腺癌细胞系（ＨＴ２９）增殖的影响。结果：ｄｂ－ｃＡＭＰ在１０－４～１０－９Ｍ范围内可促进细胞增殖，尤其在１０－６～１０－８Ｍ时，ｄｂ－ｃＡＭＰ组ＯＤ值分别为１．５０±０．１１，１．５８±０．０７，１．５７±０．１２，分别为对照组的１０．３０％，１６．１８％和１１．７６％，差异显著（Ｐ＜０．０５或０．０１）。ｄｂ－ｃＡＭＰ浓度为１０－３Ｍ时，则抑制细胞增殖，至培养第５天，ｄｂ－ｃＡＭＰ组ＯＤ为１．０５±０．１３，对照组为１．２３±０．１７，有显著差异（Ｐ＜０．０５）。ＦＣＭ结果提示，ｄｂ－ｃＡＭＰ对细胞的抑制作用，与延长细胞Ｇ１／Ｓ期有关。结果表明，ｄｂ－ｃＡＭＰ对ＨＴ２９细胞增殖有双向调节作用。作者还对其作用机制进行了探讨。     

精氨酸对梗阻性黄疸患者细胞免疫调节的意义

目的探讨精氨酸改善梗阻性黄疸细胞免疫功能和增强抗感染措施．方法梗阻性黄疸患者６６例，分为非精氨酸（Ａ组）３７例（含急性梗阻性化脓性胆管炎，ＡＯＳＣ１４例）和精氨酸组（Ｂ组）２９例（含１例ＡＯＳＣ），研究两组手术前后细胞免疫变化和感染性并发症．结果不论手术前、还是手术后，Ｂ组ＣＤ＋３，ＣＤ＋４显著高于Ａ组（Ｐ＜００１，手术前ｔ值分别为７７５和５７２，手术后ｔ值分别为８８８和１０２８），ＳＩＬＩＲ显著低于Ｂ组（Ｐ＜００１，术前ｔ＝５１４，术后ｔ＝８７６）．Ｂ组ＡＯＳＣ术后感染性并发症显著低于Ａ组（Ｐ＜００１，χ２＝１３４２）．结论精氨酸能增强机体细胞免疫功能和降低术后感染．     

用实验性心力衰竭制作持续性心房颤动模型

为探讨实验性心力衰竭（简称心衰）形成持续性心房颤动（简称房颤）的可行性，用２００～２５０ｐｐｍ的频率以ＶＯＯ方式起搏犬心室３～７周形成实验性心衰，在犬清醒状态下观察心衰前、后刺激诱发的房性快速心律失常。快速起搏右室３～７周，８条犬均发生充血性心衰，３周时体重由心衰前的２８±６ｋｇ降至２４±４ｋｇ（Ｐ＜０．０５）；左室射血分数由０．６４±０．０６降至０．２３±０．０９（Ｐ＜０．０１），右房直径由２５±３ｍｍ增至３６±６ｍｍ（Ｐ＜０．０１），心房不应期由１１６±５ｍｓ增至１３７±１２ｍｓ（Ｐ＝０．０１），不应期离散度无显著性改变（１６±１２ｍｓｖｓ２０±９ｍｓ，Ｐ＝０．２０），心房平均传导时间亦无显著性变化（６１±１９ｍｓｖｓ６６±２４ｍｓ，Ｐ＝０．２０）。１条犬于起搏后第６周夜间突然死亡。心衰前，８条犬均未诱发心房扑动，４条犬诱发短暂房颤；心衰后，８条犬均可反复诱发心房扑动和持续性房颤（持续时间超过１５ｍｉｎ，平均周长９５±５ｍｓ），最长者持续２４ｈ以上。结果表明起搏心室导致犬心衰可形成非瓣膜病性慢性房颤的实验模型。     

Role of peroxynitrite as a mediator of pathophysiological alterations in experimental pneumococcal meningitis.

This study investigated the role of peroxynitrite in an adult rat model of pneumococcal meningitis. Immunohistochemically, nitrotyrosine residues, as a marker for peroxynitrite formation, were detected perivascularly and in proximity to inflammatory cells in the subarachnoid space. Nitrotyrosine immunoreactivity was colocalized with blood-brain barrier breaching, which was visualized by fluorescence microscopy after intravenous application of Evans blue. Treatment of infected rats with uric acid (300 mg/kg intraperitoneally), a scavenger of peroxynitrite, significantly attenuated intracranial pressure, cerebrospinal fluid white blood cell count, and blood-brain barrier leakage, as indicated by Evans blue concentration in the cerebrospinal fluid (21.6+/-9.3 mm Hg, 5776+/-1790 cells/microL, 9.7+/-6.4 microgram/mL in infected, untreated rats vs. 7.2+/-1.6 mm Hg, 2004+/-904 cells/microL, 1.1+/-1.0 microgram/mL infected, uric acid-treated rats, mean+/-SD, P<.05). These data suggest that peroxynitrite plays a central role in mediating pathophysiological alterations during bacterial meningitis.     

CO及肺泡血管壁通透性在肝硬化大鼠中的变化

目的:观察CCl4诱导的肝硬化模型中,CO及肺泡血管壁通透性的变化.方法:CCl4皮下注射制备大鼠肝硬化模型,动脉插管生理多导仪记录心率、平均动脉压的变化,门静脉插管测定门静脉压力,血浆CO水平的测定用联二亚硫酸盐还原法,静脉注射伊文思蓝测定肺泡血管壁通透性.结果:CCl4成功复制肝硬化模型,显微镜下见正常肝小叶被完全...     

Effect of L—NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats

AIM: To invsstigare the effect of L-NAME on nitric oxide andgastriubtestubal motility alterations in cirrhotic ratsMETHODS: Rats with cirrhosis induced by carbontetrachloride were randomly divided into two groups, one( n= 13) receiving 0. 5 mg@ kg-1 per clay of NG-nitro-L-argininemethyl ester (L-NAME), a nitric oxide synthase inhibitor,for 10 days, whereas the other group ( n = 13) and control( n = 10) rats were administrated the same volume of 9 g@ L-1saline.Half gastric emptying time and 2 h residual rate weremeasured by SPECT, using 99m Tc-DTPA-labeled bariumsuifate as test meal. Gastrointestinal transition time wasrecorded simultaneously. Serum concentration of nitrcoxide (NO) was determined by the kinetic cadmiunreduction and colorimetric methods. ImmunohistochemicalSABC method was used to observe the expression anddistribution of three types of nitric oxide synthase (NOS)isoforms in the mt gastrointestinal tract. Western blot wasused to detect expression of gastrointestinal NOS isoforms.RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged( 124.0 ± 26.4min; 33.7± 8.9min;72.1 ± 15.3 min; P＜0.01), (12.4±0.5h; 9.5±0.3 h; 8.2±0.8 h; P＜0.01), 2h residual rate wasraised in cirrhotic rots than in controls and cirrhotic ratstreated with L-NAME(54.9± 7.6 % ,13.7 ± 3.2 %, 34.9± 10.3%, P＜ 0.01). Serum concentration of NO was significantlyincreased in cirrhotic rots than in the other groups (8.20 ± 2.48)μmol@L-1, (5.94± 1.07) μmol@L-1 ,and control (5.66± 1.60) tμmol@L-1, P＜ 0.01. NOS staining intensities which weremainly located in the gastrointestinal tissues were markedlylower in cirrhotic rats than in the controls and cirrhotic ratsafter treated with L- NAME.CONCLUSION: Gastrointestinal motility was remarkablyinhibited in cirrhotic rats, which could he alleviated by L-NAME. Nitric oxide may play an important role in theinhibition of gastrointestinal motility in cirrhotic rats.     

丁基苯酞对缺血性脑损伤模型大鼠血脑屏障的影响

目的观察大鼠全脑缺血后血脑屏障的改变以及丁基苯酞的干预作用,探讨其对缺血性脑损伤的防护作用机制。方法选择120只SD大鼠,随机分为假手术组24只、脑缺血组24只、丁基苯酞组72只。采用四血管结扎的全脑缺血模型,制模成功后丁基苯酞组大鼠按腹腔注射剂量又分为丁基苯酞0.3 mg/kg组24只、丁基苯酞1.0mg/kg组24只、丁基苯酞3.0 mg/kg组24只;检测脑组织依文思蓝(EB)含量、免疫组织化学法检测脑组织血管内皮生长因子(VEGF)表达、心脏取血计数循环内皮细胞数。结果与假手术组比较,脑缺血组大鼠脑组织EB含量、VEGF表达、循环内皮细胞数明显升高(P<0.05,P<0.01);与脑缺血组比较,丁基苯酞各剂量组大鼠脑组织EB含量、VEGF表达、循环内皮细胞数明显降低,以丁基苯酞3.0 mg/kg组最明显(P<0.05,P<0.01)。结论丁基苯酞通过降低大鼠全脑缺血后脑组织VEGF表达、降低循环内皮细胞数,从而降低血脑屏障的通透性,对缺血性脑损伤有保护作用。     

High-density lipoproteins reduce the effect of endotoxin on cytokine production and systemic hemodynamics in cirrhotic rats with ascites

BACKGROUND/AIMS: Hypersensitivity to endotoxin is a recognized feature in cirrhosis. High-density lipoproteins (HDL) have a high capacity to inactivate endotoxin. The aim was to determine if HDL reduces the effect of endotoxin on cytokine production and systemic hemodynamics in experimental cirrhosis. METHODS: The study was performed in control and rats with carbon-tetrachloride induced cirrhosis with ascites. Hemodynamic parameters were determined before and after several doses of endotoxin. The effects of 25 microg/kg of endotoxin on the serum concentration of TNFalpha and mean arterial pressure (MAP) were determined after treatment with HDL (80 mg/kg) or saline. RESULTS: Whereas endotoxin decreased MAP only at doses of 100 and 1000 microg/kg in control rats, in cirrhotic rats significant hypotension occurred at doses of 25, 50, 100 and 1000 microg/kg. Following the administration of endotoxin (25 microg/kg) the serum levels of TNFalpha were 140 times higher in cirrhotic than in control rats (89?835+/-21?090 vs. 625+/-137 pg/ml; P<0.001). Serum TNFalpha was 80% lower in cirrhotic rats pretreated with HDL (18?890+/-5012 pg/ml; P<0.001) than in those pretreated with saline. The administration of endotoxin (25 microg/kg) was associated with a significant lower decrease of MAP in cirrhotic rats pretreated with HDL than in those receiving saline (11.9+/-3.5 vs. 24.7+/-4.3%; P<0.05). CONCLUSIONS: HDL attenuates the increased effect of endotoxin on cytokine production and systemic hemodynamic in cirrhosis.     

Cerebral blood flow autoregulation and edema formation during pregnancy in anesthetized rats

Eclampsia is considered a form of hypertensive encephalopathy in which an acute elevation in blood pressure causes autoregulatory breakthrough, blood-brain barrier disruption, and edema formation. We hypothesized that pregnancy predisposes the brain to eclampsia by lowering the pressure of autoregulatory breakthrough and enhancing cerebral edema formation. Because NO production is increased in pregnancy, we also investigated the role of NO in modulating autoregulation. Cerebral blood flow autoregulation was determined by phenylephrine infusion and laser Doppler flowmetry. Four groups were studied: untreated nonpregnant (n=7) and late-pregnant (days 19 to 21; n=8) Sprague-Dawley rats and nonpregnant (n=8) and late-pregnant (n=8) animals treated with an NO synthase inhibitor (N(G)-nitro-l-arginine methyl ester; 0.5 to 0.7 g/L). Brain water content and blood-brain barrier permeability to sodium fluorescein were determined after breakthrough. Pregnancy caused no change in autoregulation or the pressure of breakthrough. However, treatment with the NO synthase inhibitor significantly increased the pressure of autoregulatory breakthrough (nonpregnant: 183.6+/-3.0 mm Hg versus 212.0+/-2.8 mm Hg, P<0.05; late-pregnant: 180.8+/-3.2 mm Hg versus 209.3+/-4.7 mm Hg, P<0.05). After autoregulatory breakthrough, only late-pregnant animals showed a significant increase in cerebral edema formation, which was attenuated by NO synthase inhibition. There was no difference in blood-brain barrier permeability between nonpregnant and late-pregnant animals in response to acute hypertension, suggesting that pregnancy may predispose the brain to eclampsia by increasing cerebral edema through increased hydraulic conductivity.     

Mixed endothelin receptor antagonist, SB209670, decreases portal pressure in biliary cirrhotic rats in vivo by reducing portal venous system resistance

BACKGROUND/AIMS: This study aimed to evaluate the hemodynamic effects of endothelin-1 or mixed endothelin receptor antagonist, SB209670 in cirrhotic rats, and to elucidate the role of endothelin in cirrhotic portal hypertension. METHODS: Secondary biliary cirrhosis was induced by bile duct ligation. Hemodynamics were studied using the radioactive microsphere technique. RESULTS: Plasma and hepatic endothelin levels in cirrhotic rats were significantly higher than those in normal rats (plasma, 9.0+/-1.3 vs. 2.6+/-0.5 pg/ml, p<0.001; liver, 74.8+/-13.3 vs. 12.6+/-2.5 pg/g wet tissue, p<0.001). Intraportal administration of endothelin-1 (3 nmol/kg) progressively raised portal pressure without an initial transient reduction, which was observed in systemic arterial pressure, in both cirrhotic and normal rats. SB209670 (5.4 micromol/kg) reduced portal pressure in cirrhotic rats (-19+/-5%, p<0.01) without modifying systemic arterial pressure and renal blood flow, but not in normal rats. This reduction was associated with reduced portal venous system resistance (vehicle, 2.5+/-0.2 vs. SB209670, 1.7+/-0.1 mmHg x min x 100 g bw/ml, p<0.01), but not with change in portal venous inflow and collateral blood flow. CONCLUSIONS: Mixed endothelin antagonist, SB209670, decreased portal pressure by reducing portal venous system resistance without modifying systemic arterial pressure and renal blood flow in cirrhotic rats. This result, together with the findings that plasma and hepatic endothelin levels were elevated in cirrhotic rats and that exogenous endothelin-1 increased portal pressure, provides further support for a role of endothelin in portal hypertension and suggests a potential use of mixed endothelin antagonist in the pharmacological treatment of portal hypertension.     

低氧性肺动脉高压形成中气体信号分子硫化氢对一氧化碳/血红素加氧酶途径的影响

目的研究新型气体信号分子硫化氢(H2S)在大鼠低氧性肺动脉高压形成中对一氧化碳(CO)/血红素加氧酶(HO1)体系的调节作用,以深入探讨H2S在大鼠低氧性肺动脉高压形成中的病理生理意义。方法将27只大鼠随机分为4组对照组(7只),低氧组(7只),低氧 硫氢化钠(NaHS)组(7只),低氧 炔丙基甘氨酸(PPG)组(6只)。低氧21d后分别测定肺动脉平均压、血浆H2S及CO含量,观察肺动脉平滑肌HO1蛋白及HO1mRNA表达。结果随着低氧性肺动脉高压的形成,血浆H2S的含量显著下降,低氧组[(196±22)μmol/L]与对照组[(294±26)μmol/L]比较差异有显著性(P<005);而CO含量、大、中、小各级肺动脉平滑肌HO1蛋白表达[对照组、低氧组分别为(0313±0020)μmol/L、(0348±0021)μmol/L,066±008、079±008,064±005、077±008,054±005、076±009]及其mRNA表达(对照组、低氧组分别为0573±0148、0813±0052,0532±0131、0831±0043,0473±0102、0819±0032)显著升高(P均<005);外源性给予H2S的供体后,低氧 NaHS组血浆H2S含量[(324±33)μmol/L]显著高于低氧组[(196±22)μmol/L,P<005],肺动脉压显著下降(P<005),且血浆CO含量[(0393±0032)μmol/L]、大、中、小各级肺动脉平滑肌HO1蛋白表达(088±004、089±005、089±006)及mRNA表达(0913±0022、0     

Rosiglitazone and pulmonary oedema: an acute dose-dependent effect on human endothelial cell permeability

AIMS/HYPOTHESIS: Peripheral and pulmonary oedema has emerged as the most common drug-related side effect of rosiglitazone in clinical practice, but the underlying mechanisms are not clear. Fluid retention and changes in vascular tone could contribute to oedema formation, but the interpretation of clinical and in vivo studies is particularly difficult and the direct effects of thiazolidinediones on endothelial barrier function have not been previously reported. METHODS: Human pulmonary artery endothelial cells were seeded and grown on 0.4 microm collagen-coated filters to form a tight monolayer (transendothelial electrical resistance 9-11 ohms.cm(-2) after 2-3 days). Transendothelial albumin flux (expressed as the percentage clearance of albumin relative to control) was measured using Evans blue-labelled albumin after exposure to rosiglitazone 1-100 micromol/l for 1 h to 48 h, and after removal of drug from the monolayer. RESULTS: Incubation of pulmonary artery endothelial cells with rosiglitazone for 4 h produced immediate concentration-dependent increases in transendothelial albumin flux: e.g., relative to control (100%), 113%+/-13% (1 micromol/l), 215%+/-37% (10 micromol/l, p=0.01) and 461%+/-96% (100 micromol/l, p=0.002) (n=12). There was no effect after 1 h. The acute hyperpermeability response to rosiglitazone, maximal after 4 h, was fully reversible after washing the monolayer. After incubation for 24 to 48 h the effect of rosiglitazone on pulmonary endothelial permeability tended to subside: e.g., 210%+/-59% (24 h) for rosiglitazone 100 micromol/l (p=0.06). CONCLUSION/INTERPRETATION: Exposure to high-therapeutic concentrations of rosiglitazone causes a reversible fourfold increase in pulmonary endothelial permeability which could be clinically relevant especially at higher doses and at times of peak plasma drug concentration.     

Adrenomedullin in cirrhotic and non-cirrhotic portal hypertension

AIM:Adrenomedullin (ADM) is a potent vasodilator peptide.ADM and nitric oxide (NO) are produced in vascular endothelial cells. Increased ADM level has been linked to hyperdynamic circulation and arterial vasodilatation in cirrhotic portal hypertension (CPH). The role of ADM in non-cirrhotic portal hypertension (NCPH) is unknown, plasma ADM levels were studied in patients with NCPH, compensated and decompensated cirrhosis in order to determine its contribution to portal hypertension (PH) in these groups.METHODS: There were 4 groups of subjects. Group 1consisted of 27 patients (F/M: 12/15) with NCPH due to portal and/or splenic vein thrombosis (mean age: 41±12years), group 2 consisted of 14 patients (F/M: 6/8) with compensated (Child-Pugh A) cirrhosis (mean age: 46±4),group 3 consisted of 16 patients (F/M: 6/10) with decompensated (Child-Pugh C) cirrhosis (mean age: 47±12).Fourteen healthy subjects (F/M: 6/8) (mean age: 44±8) were used as controls in Group 4. ADM level was measured by ELISA. NO was determined as nitrite/nitrate level by chemoluminescence.RESULTS: Adl level in Group 11 (236±61.4 pg/mL) was significantly higher than that in group 2 (108.4±28.3 pg/mL)and group 4 (84.1±31.5 pg/mL) (both P＜0.0001) but was lower than that in Group3 (324±93.7 pg/mL) (P=0.002). NO level in group 1 (27±1.4 μmol/L) was significantly higher than that in group 2 (19.8±2.8 μmol/L) and group 4 (16.9±1.6μmol/L) but was lower than that in Group 3 (39±3.6 μmol/L)(for all three P＜0.0001). A strong correlation was observed between ADM and NO levels (r=0.827, P＜0.0001).CONCLUSION: Adrenomedullin and NO levels were high in both non-cirrhotic and cirrhotic portal hypertension and were closely correlated, Adrenomedullin and NO levels increased proportionally with the severity of cirrhosis, and were significantly higher than those in patients with NCPH.Portal hypertension plays an important role in the increase of ADM and NO. Parenchymal damage in cirrhosis may contribute to the increase in these parameters.