贝那普利抑制家兔腹主动脉瘤形成的实验研究

目的观察贝纳普利干预对家兔腹主动脉瘤(AAA)形成的影响并探讨其可能机制。方法将雄性家兔24只按灌注液(盐水,弹力蛋白酶,弹力蛋白酶+贝纳普利)随机分为3组,观察灌注后各组腹主动脉的形态学变化;行HE染色及VG弹力染色观察其组织学改变;用Western Blot法检测基质金属蛋白酶9(MMP-9)的表达;RT-PCR检测MMP-9的mRNA的表达;明胶酶谱法检测MMP-9的活性。结果术后7d,3组腹主动脉平均扩张率分别为7.50%(盐水灌注组,A组),120.62%(弹力蛋白酶灌注组,B组),39.20%(贝纳普利干预组,C组)。C组均未形成腹主动脉瘤,其中层弹力纤维含量及结构完整性优于B组(P0.01),且血管壁炎症细胞浸润减少。B组MMP-9表达及活性增强,C组MMP-9蛋白及mRNA表达明显减弱(P0.01),其活性亦明显降低(P0.01)。结论贝纳普利能显著抑制家兔AAA模型形成;其机制可能与抑制炎症浸润,多水平下调细胞外基质降解,保存弹力纤维有关。     

氯血红素对腹主动脉瘤形成的抑制作用的实验研究

目的探讨血红素氧合酶-1（HO-1）基因在大鼠腹主动脉瘤（AAA）形成中的作用及机制。方法大鼠随机分成氯血红素组（实验组）和生理盐水组（对照组），建立腹主动脉瘤模型，于术后7d取材，观察主动脉的扩张情况，免疫组化染色检测细胞间黏附分子（ICAM）-1及HO-1的蛋白表达。原位分子杂交检测动脉壁中HO-1mRNA的表达。结果实验组动脉扩张受到抑制，未形成AAA（P〈0．01）；其HO-1mRNA和HO-1的蛋白表达增强（P〈0．05）；ICAM-1蛋白表达受到抑制（P〈0．01）。结论氯血红素通过促进HO-1过表达，抑制ICAM-1蛋白表达，从而抑制腹主动脉瘤的形成．     

单核细胞趋化蛋白-1基因表达在实验性腹主动脉瘤发病过程中的意义

目的　探讨实验性腹主动脉瘤 (abdominalaorticaneurysm ,AAA)不同阶段 ,动脉壁中单核细胞趋化蛋白 1(monocytechemotacticprotein 1,MCP 1)基因的表达及意义。方法　经腔内导管灌注制成大鼠AAA模型 ,分别于 3d、1、2、4周切取腹主动脉 ,应用原位杂交、Western蛋白质印迹、CD6 8免疫组织化学染色观察AAA发病不同时期动脉壁中MCP 1基因表达情况及巨噬细胞的浸润程度。结果　MCP 1mRNA表达于灌注后 1周达高峰 ,阳性率为 39 5 %± 7 5 % ;CD6 8、MCP 1蛋白表达均于灌注后 2周达高峰 ,与其他时段相比 ,差异有非常显著意义 (P <0 0 1)。结论　动脉壁中MCP 1基因做为AAA发病过程中的一种早期表达基因 ,诱导了单核巨噬细胞在动脉壁的黏附、浸润 ,对AAA的发生、发展起着重要的促进作用。     

缺氧诱导因子-1α及相关基因在破裂性腹主动脉瘤中的表达及意义

目的研究缺氧诱导因子(hypoxia-inducible factor-1α,HIF-1α)信号转导通路在破裂性腹主动脉瘤(ruptured abdominal aorta aneurysm,RAAA)中的表达,探讨AAA破裂的分子基础。方法选取RAAA标本18例,以20例AAA标本作对照。采用Northern杂交、Western蛋白印迹及免疫组织化学方法检测HIF-1α的mRNA及蛋白产物表达,Western蛋白印迹和免疫组织化学方法检测血管内皮生长因子(VEGF)的表达,免疫组织化学抗CD34染色法检测微血管密度(microvessel density, MVD)。结果 RAAA组织中HIF-1α mRNA表达明显高于AAA组(P<0．01),免疫组化染色表明 HIF-1α阳性细胞百分率为(40．9±10．8)％,与AAA(17．6±5．2)％比较差异有统计学意义(P< 0．01);VEGF表达亦明显增强(P<0．01),与HIF-1α表达呈显著正相关(r值为0．725,P<0．01)。 HIF-1α阳性表达主要分布在AAA中层平滑肌细胞及外膜。RAAA中微血管密度明显增多(P< 0．01)。结论 HIF-1α及其相关基因过表达在RAAA的分子机制中可能发挥重要作用。     

腹主动脉瘤发病中低氧诱导因子-1α介导血管平滑肌细胞凋亡的研究

目的　研究腹主动脉瘤 (AAA)发病不同时期动脉壁中低氧诱导因子 (HIF) 1α的表达及与血管平滑肌细胞 (SMC)凋亡的关系。方法　将 60只Wistar大鼠制成AAA模型 ,分别于术后 1、3、7、14、2 1d切取腹主动脉 ,应用原位DNA片段末端标记 (TUNEL)检测SMC中的凋亡信号 ,用免疫组织化学方法检测HIF 1α及凋亡相关基因p5 3、bcl 2的蛋白表达。结果　HIF 1α的表达于术后 3d达表达高峰 ,为 (18.4± 3 .5 ) % ;术后 7d左右是TUNEL染色及p5 3蛋白表达的高峰时段 ,分别为(19.8± 3 .8) %、(17.6± 3 .3 ) % ;bcl 2蛋白在术后 1d时表达较强烈 ,为 (14 .1± 2 .9) %。结论　HIF 1α参与了腹主动脉缺血缺氧状态下的继发损害过程 ,并可通过调节动脉壁中p5 3、bcl 2的蛋白表达水平促进SMC的凋亡 ,是AAA发病过程中一个重要的中间因子。     

缺氧诱导因子-1α及其相关基因在腹主动脉瘤中的表达及意义

目的研究缺氧诱导因子(HIF)-1α信号转导通路及其相关基因在腹主动脉瘤(AAA)中的表达,探讨AAA的发病机制。方法选取AAA标本22例,以5例腹主动脉(NA)标本作对照。采用Northern杂交、Western蛋白印迹及免疫组织化学方法检测HIF-1α的mRNA及蛋白产物表达,Western蛋白印迹或免疫组织化学方法检测血管内皮生长因子(VEGF)及半胱氨酸蛋白酶(caspase)-3的表达,免疫组织化学抗CD34染色法检测微血管密度(MVD)。结果 AAA组织中HIF-1α的mRNA及蛋白产物表达明显高于NA(P<0.01);caspase-3和VEGF表达亦明显增强(P<0.01),与HIF-1α表达呈显著正相关(r值分别为0.783和0.693,P<0.01)。HIF-1α表达主要分布在AAA中层血管平滑肌细胞及外膜处,与caspase-3和VEGF的分布部位基本一致。AAA中微血管密度明显增加(P<0.01))。结论HIF-1α在AAA疾病进展过程中可能发挥重要作用,其作用机制可能是通过调控VEGF或caspase-3的表达而实现的。     

梗阻性黄疸大鼠肺血红素氧化酶-1 mRNA表达及一氧化碳含量的变化

目的探讨梗阻性黄疸时肺血红素氧化酶(HO)1mRNA表达及一氧化碳(CO)含量变化的意义。方法健康雄性Wistar大鼠48只,随机等分成4组假手术对照组(CG)、梗阻性黄疸7d组、梗阻性黄疸14d组和梗阻性黄疸21d组。应用原位杂交技术行HO1mRNA表达检测,采用双波长分光光度计法测定大鼠血浆及肺组织匀浆中CO含量。结果7d组大鼠肺泡上皮细胞HO1mRNA表达呈中度阳性,14d组支气管黏膜上皮细胞、血管内皮细胞中HO1mRNA高表达,而21d组其表达进一步增强;14d和21d组血浆中CO含量均较CG组增高(P<0.05,P<0.01),梗阻性黄疸各组肺组织匀浆中CO含量均较CG组明显升高(P<0.01);7、14及21d组肺组织匀浆中CO含量的升高分别与同时间组肺HO1mRNA表达变化呈显著正相关。结论梗阻性黄疸时肺HO1mRNA的高表达及CO产生增多,有助于扩张肺血管并改善肺微循环,从而减轻梗阻性黄疸时肺损害的程度。     

大鼠性别对腹主动脉瘤模型建立的影响

目的通过对雌、雄性大鼠腹主动脉瘤(abdominal aortic aneurysm,AAA)动物模型组织中基质金属蛋白酶-2、9(matrix metalloproteinases-2、9,MMP-2、9)mRNA及蛋白表达的对比,探讨性别差异对腹主动脉瘤模型形成的影响。方法雌、雄Wistar大鼠各15只,分别用弹性蛋白酶、生理盐水灌注肾下腹主动脉制作AAA模型。14 d后取出腹主动脉,用免疫组化、适时RT-PCR测定动脉瘤组织MMP-2、9的mRNA及蛋白的表达。结果雌性大鼠实验组与雄性大鼠实验组比较,动脉瘤扩张率分别为(104±6)％和(179±11)％(P<0．01)、MMP-2 mRNA的相对表达量分别为0．02±0．01和0．46±0．25(P<0．01)、MMP-9 mRNA的相对表达量分别为0．42±0．24和4．30±2．87 (P<0．01)、MMP-2的表达率分别为(22±5)％和(46±9)％(P<0．01)、MMP-9的表达率分别为(26±2)％和(43±3)％(P<0．01)。结论在腹主动脉瘤形成的过程中雌性大鼠的MMP-2、9的mRNA和蛋白的表达以及炎性细胞的浸润均明显少于雄性大鼠,导致动脉瘤扩张率出现明显差异。     

丹参酮ⅡA抑制腹主动脉瘤基质金属蛋白酶-2及诱导型一氧化氮合酶的研究

目的 观察丹参酮ⅡA对胰弹力蛋白酶灌注制作的大鼠腹主动脉瘤(AAA)模型中基质金属蛋白酶-2( MMP-2)和诱导型一氧化氮合酶(iNOS)的抑制作用.方法 将SD雄性大鼠36只随机分成实验组、对照组、空白组3组,每组12只.实验组与对照组应用胰弹力蛋白酶灌注方法制作AAA模型,空白组给予生理盐水灌注.实验组全程接受腹腔内注射丹参酮ⅡA2mg/(天·只),对照组与空白组给予生理盐水注射.术前和术后第5、12、18、24天使用彩色超声仪测量动脉瘤最大处内径,并测量动脉收缩压.术后24 d取腹主动脉组织标本观察组织学变化,应用免疫组织化学、Western blot、逆转录-聚合酶链反应(RT-PCR)方法进行定量观察.结果 术后第1周起实验组腹主动脉直径明显小于对照组(P＜0.01),且各组血压无明显变化(P＞0.05).实验组标本中弹力纤维含量明显高于对照组(P＜0.01),而MMP-2和iNOS蛋白表达则明显较对照组减少(P＜0.01).实验组MMP-2 mRNA表达较对照组明显抑制(P＜0.01).结论 丹参酮ⅡA能够通过下调MMP-2和iNOS表达而抑制大鼠AAA的扩张.     

足细胞分子高表达致阿霉素肾病大鼠发生蛋白尿

目的 动态观察足细胞裂孔隔膜复合体分子nephrin、podocin、CD2AP及α-actinin-4在阿霉素肾病大鼠蛋白尿发生发展中的表达变化，探讨其在蛋白尿发生发展中的分子行为及其机制。方法 尾静脉注射阿霉素建立阿霉素肾病大鼠模型，3、7、14、28 d每组处死6只大鼠留取肾脏标本。应用间接免疫荧光染色、实时定量PCR、Western 印迹分别检测各个时间点nephrin、podocin、CD2AP、α-actinin-4的分布、mRNA和蛋白表达量的变化。结果 (1)14 d肾病组大鼠24 h尿蛋白显著高于对照组(P < 0.01)，增高持续到28 d。(2)透射电镜显示14 d肾病组足突不同程度变宽，28 d足突弥漫性融合。(3)与对照组相比，从第7天开始肾病组nephrin和podocin染色从沿肾小球毛细血管袢线样分布向不连续粗颗粒样的分布模式转变；CD2AP节段染色增强区逐渐扩大，有的区域呈斑片状和连续线状增强；α-actinin-4从沿肾小球毛细血管袢均匀的点线样分布向不均匀粗颗粒的分布转变，而且随时间进展这种转变逐渐加重。(4)与对照组相比，肾病组于7 d时nephrin mRNA表达显著增高(P < 0.01)；podocin mRNA表达14 d时显著增高(P < 0.05)，直至28 d(P < 0.05)；CD2AP mRNA表达28 d时显著增高(P < 0.05)。(5)与对照组相比，肾病组nephrin蛋白表达28 d时显著增高(P < 0.05)；podocin蛋白表达于7 d时显著增高(P < 0.05)，而28 d时又显著降低(P < 0.05)；CD2AP蛋白表达于14 d时显著增高(P < 0.05)，直至28 d (P < 0.05)。(6)α-actinin-4 mRNA与蛋白表达在实验过程中未出现明显变化。结论 nephrin、podocin和CD2AP的表达增加及分布异常是导致阿霉素肾病大鼠蛋白尿发生发展的分子机制，而分子表达的增加是足细胞抵抗损伤的一种代偿反应。     

直肠癌术前动脉插管化疗后手术时机的选择

探讨直肠癌患者术前动脉管化疗后的手术时机。方法对２７例Ｄｕｋｅｓ’Ｂ－Ｃ期直肠癌患者,选择肠系膜下动脉或左髂内动脉,以５－氟脲嘧啶６００ｍｇ／ｍ＾２、丝裂霉素１５ｍｇ／ｍ＾２、表阿霉素３０ｍｇ／ｍ＾２、丝裂霉素１５ｍｇ／     

他莫昔芬对大鼠腹主动脉瘤形成的抑制作用

目的 观察他莫昔芬对大鼠腹主动脉瘤(AAA)形成的影响及作用机制.方法 40只雄性Wistar大鼠随机分成2组,实验组他莫昔芬预给药7 d(每天15 mg/kg体重),建立A从灌注模制.术后7 d切取腹主动脉.一计算腹主动脉直径变化率,苏木素-伊红(HE)染色观察动脉壁炎性细胞浸润,Verhoff染色观察动脉壁弹性纤维,免疫组织化学观察动脉壁基质金属蛋白酶(MMP)-2,9及巨噬细胞的表达.结果 他莫昔芬明显抑制AAA的形成,抑制率95%～99%.动脉壁内炎性细胞浸润明显减少,弹力纤维破坏受到抑制,MMP-2,9及巨噬细胞的表达受到抑制.结论 他莫昔芬通过抑制大鼠腹主动脉壁内早期的炎症反应和MMPS的表达,抑制大鼠AAA的形成.     

雌激素预防大鼠同种肾移植慢性排斥反应的实验研究

目的 探讨雌激素对移植肾慢性排斥反应的影响。方法 以Fisher大鼠作供者,雌性Lewis大鼠作受者进行同种肾移植,为排除排卵周期及相应的内源性性激素变化的影响,肾移植均在非排卵期进行,后治疗组大鼠隔日给予25μg/kg雌二醇皮下注射。移植后16周作肾功能、移植肾组织学及免疫组化检测,测定肾组织中转化生长因子及β－机动蛋白mRNA的表达。结果 与对照组比较,移植后治疗组24d尿蛋白持续保持较低的水平（P＜0.01）,血清肌酐水平降低（P＜0.01）,肌酐清除率升高（P＜0.01）,移植肾组织管内膜增厚、肾小球硬化和间质纤维化程度减轻（P均＜0.01）,淋巴细胞和单核／巨噬细胞浸润减少（P＜0.01）,细胞间粘附分子（ICAM－1）、转化生长因子（TGF－β1）的mRNA表达减少（P均＜0.01）。结论 雌激素对移植肾功能有保护作用,其机理与影响上述细胞因子在移植肾的表达有关,提示雌激素可能为一类潜在的抗慢性排斥反应药物。     

Hemoglobin-based oxygen carrier induces hepatic heme oxygenase 1 expression in Kupffer cells

BACKGROUND: Kupffer cells (liver macrophages) are a key initiator of inflammation following hepatic insults such as infection, ischemia/reperfusion, and rejection. Heme oxygenase 1 (HO-1) is protective against inflammatory injury. A hemoglobin-based oxygen carrier (HBOC) has been shown to prevent organ inflammation from hemorrhagic shock as well as induce HO-1 at the cellular level. Therefore, we hypothesize that HBOC can induce Kupffer cell HO-1 production. METHODS: Mice administered 20% blood volume HBOC or saline intravenously were sacrificed at 0, 12, 24, 48 hours (n = 4-6/group). Hepatic protein underwent Western blotting for HO-1 and heat shock protein 72. Hepatic frozen sections underwent immunofluorescent staining for HO-1/CD68. RESULTS: Following HBOC injection, hepatic HO-1 fold change peaked at 12 hours (7.3 +/- 0.8) (p < .01), remained increased at 24 hours (4.7 +/- 0.4) (p < .01), and returned to baseline by 48 hours. HSP72 expression was unaffected in all groups. Twleve-hour liver section immunostaining confirmed significant induction of HO-1 by HBOC. Double staining for HO-1 and CD68 identified Kupffer cells as the majority of cells expressing HO-1. CONCLUSION: HBOC induces hepatic HO-1 expression in Kupffer cells without heat shock protein response. These data provide the basis for further investigation into a clinical therapy to induce Kupffer cell HO-1 expression with the goal of attenuating the hepatic immunoresponse to various insults.     

Obstruction of St Jude Medical valves in the aortic position: histology and immunohistochemistry of pannus

OBJECTIVE: This study aims to reveal the morphological, histological, and immunohistochemical mechanism of pannus formation using resected pannus tissue from patients with prosthetic valve dysfunction. METHOD: Eleven patients with prosthetic valve (St Jude Medical valve) dysfunction in the aortic position who underwent reoperation were studied. We used specimens of resected pannus for histological staining (hematoxylin and eosin, Grocott's, azan, elastica van Gieson) and immunohistochemical staining (transforming growth factor-beta, transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, epithelial membrane antigen, CD34, factor VIII, CD68KP1, matrix metalloproteinase-1, matrix metalloproteinase-3, and matrix metalloproteinase-9). RESULTS: Pannus without thrombus was observed at the periannulus of the left ventricular septal side; it extended into the pivot guard, interfering with the movement of the straight edge of the leaflet. The histological staining demonstrated that the specimens were mainly constituted with collagen and elastic fibrous tissue accompanied by endothelial cells, chronic inflammatory cells infiltration, and myofibroblasts. The immunohistochemical findings showed significant expression of transforming growth factor-beta, transforming growth factor-beta receptor 1, CD34, and factor VIII in the endothelial cells of the lumen layer; strong transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, and epithelial membrane antigen in the myofibroblasts of the media layer; and transforming growth factor-beta, transforming growth factor-beta receptor 1, and CD68KP1 in macrophages of the stump lesion. CONCLUSIONS: Pannus appeared to originate in the neointima in the periannulus of the left ventricular septum. The structure of the pannus consisted of myofibroblasts and an extracellular matrix such as collagen fiber. The pannus formation after prosthetic valve replacement may be associated with a process of periannular tissue healing via the expression of transforming growth factor-beta.     

Expression of ICAM-1 and CD11b after experimental spinal cord injury in rats

We have performed an immunohistochemical study on the expression of the adhesion molecules ICAM-1 and CD11b 1 h to 1 week following a compression injury to the rat spinal cord. The spinal cord of control animals showed ICAM-1 expression in some vessels and in the leptomeninges. Mechanical compression of the spinal cord induced an endothelial upregulation of ICAM-1 that was maximal in rats surviving 1-2 days after injury. This reaction was seen at the center of the lesion as well as in the perifocal zones. Apart from the endothelial upregulation, increased ICAM-1 expression also was found in leptomeningeal and ependymal cells of traumatized animals. In control animals resting microglial cells were moderately CD11b immunoreactive. Trauma induced a rapid microglial upregulation of CD11b in the white matter that was evident even at 1 h after injury. By 1 day to 1 week posttrauma conformational changes consistent with microglial activation, i.e., transformation into phagocytic microglial cells, were seen in the white matter. In the gray matter, CD11b immunohistochemistry revealed massive infiltration of phagocytic microglial cells and macrophages in animals surviving 1 day to 1 week. Intravascular and infiltrating leukocytes were intensely CD11b immunopositive. As reflected by CD11b immunohistochemistry, the maximal infiltration of polymorphonuclear leukocytes occurred at 2 days after the insult. Endothelial upregulation of ICAM-1 facilitates adhesion and extravasation of leukocytes by binding to the counterreceptor CD11b. Knowledge regarding the expression and cellular distribution of such molecules after central nervous system trauma is important since inflammatory mechanisms have been suggested to be involved in secondary neurological damage and thus constitute potential targets of therapy.     

Expression of CD44 in rat liver allografts during rejection

As CD44 is believed to be a homing receptor involved in lymphoid trafficking and inflammatory responses, it is expected to be closely linked to transplant rejection. In this study, the expression of CD44 during liver transplant rejection was compared with the expression of lymphocyte-function associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1), which play an essential role in cell interactions and the initiation of immune responses. Male Brown Norway (BN) and Lewis (LEW) rats were used as donors and recipients, respectively. Orthotopic liver transplantation (OLTX) was done using the cuff technique of Kamada and Calne. Animals were killed on days 3, 5, and 7 after OLTX, and a piece of tissue from each of the liver grafts was obtained. Immunohistochemical staining was used to investigate the expression of CD44, ICAM-1, and LFA-1. CD44 was strongly expressed in portal areas of the rejected liver, and LFA-1 and ICAM-1 were expressed mainly on sinusoids and hepatocytes. These findings indicate that CD44 is closely involved in lymphocyte infiltration, which is dominant in portal areas, and that lymphocyte infiltration during the rejection process may involve a homing mechanism. Received for publication on Oct. 17, 1997; accepted on Oct. 21, 1997