热休克预处理对大鼠缺血再灌注心肌保护作用机制的探讨

目的:观察心肌缺血再灌注时P-选择素（Ps）表达情况；探讨热休克蛋白(HSP)对缺血再灌注心肌Ps及细胞凋亡表达的影响。 方法:成年雌性Wistar（n=40）大鼠随机分为3组。热休克组全麻后高热处理造成热休克动物模型，对照组及假手术组仅予全麻处理。24 h后热休克组及对照组结扎左冠状动脉前降支(LAD)1 h，再灌注2 h造成心肌缺血再灌注动物模型。假手术组只于LAD处穿线而不结扎。术毕测心梗范围、HSP70、Bax、Bcl-2、Ps、凋亡细胞及血清CK-MB。 结果:热休克组HSP70表达高于对照组及假手术组(P<0.05)，后两组无明显差别(P>0.05)；热休克组心梗范围小于对照组(P<0.05)，CK-MB值低于对照组(P<0.01)，凋亡细胞、Bax及Ps表达低于对照组(P<0.05)，两组Bcl-2表达无显著差别(P>0.05)；假手术组无Ps表达。 结论:HSP70可抑制缺血再灌注诱导的心肌细胞凋亡，抑制Bax表达致Bax/Bcl-2比值下降为其机制之一；Ps参与心肌缺血再灌注损伤；HSP70可能有抑制心肌Ps表达的作用，这或许是热休克预处理对大鼠缺血再灌注心肌的另一保护机制。     

梗死灶周围心肌C3G蛋白表达增加参与了异丙肾上腺素诱导的梗死后心脏重塑恶化的发病机制

 目的 通过观察梗死灶周围心肌C3G蛋白的表达及异丙肾上腺素(ISO)对其的影响,探讨梗死灶周围心肌C3G蛋白是否参与了异丙肾上腺素诱导的梗死后心脏重塑恶化的发病机制。方法 按Litwin方法建立心肌梗死(心梗)及假手术模型。 术后7天仍存活的雄性SD大鼠分为心梗组,假手术组,心梗ISO组,假手术ISO组。其中,心梗组及假手术组给予生理盐水5ml/kg每三天一次, 腹腔注射,至干预后12周;心梗ISO组及假手术ISO组给予ISO 5mg/kg每三天一次, 腹腔注射,余方法同上。免疫印迹检测梗死灶周围心肌C3G 蛋白的表达。结果 干预后12周, 梗死灶周围心肌C3G蛋白表达积分光密度标化值分别为：心梗组（1.14±0.29, n=8）, 假手术组（0.90±0.10,n=6）, 心梗ISO组（1.51±0.18,n=10 ）, 假手术ISO组（0.97±0.26, n=8）。心梗组较假手术组、 心梗ISO组较假手术ISO组、及心梗ISO组较心梗组梗死灶周围心肌C3G蛋白的表达均显著增高（P＜0.05）。 结论 梗死灶周围心肌C3G蛋白表达显著增加, 而ISO可使C3G蛋白表达更显著增加; C3G蛋白表达增加参与了梗死后心室重塑,缺血性心肌病及心力衰竭的发病机制,且C3G蛋白表达进一步增加参与了ISO诱导的梗死后心室重塑,缺血性心肌病及心力衰竭恶化的发病机制。     

硫化氢供体对大鼠高肺血流性肺动脉高压中内皮素-1及结缔组织生长因子表达的影响

目的：探讨硫氢化钠（NaHS）对大鼠高肺血流性肺动脉高压中内皮素-1(ET-1)及结缔组织生长因子(CTGF)表达的影响。方法:32只雄性SD大鼠随机分为分流组（n=8）、分流+NaHS组（n=8）、假手术组（n=8）和假手术+NaHS组（n=8）。对分流组和分流+NaHS组大鼠行腹主动脉-下腔静脉穿刺建立高肺血流动物模型。分流11周后，分别测定大鼠肺动脉收缩压（SPAP）、血浆ET-1含量、肺组织硫化氢（H2S）含量、肺组织ET-1mRNA的表达及肺动脉CTGF蛋白的表达。结果:分流11周，大鼠SPAP明显高于假手术组(P<0.05)；分流组大鼠肺组织ET-1mRNA表达、血浆ET-1含量以及肺腺泡肌型动脉CTGF表达明显高于假手术组；肺组织H2S含量明显低于假手术组(P<0.05)；应用NaHS干预11周，分流+NaHS组大鼠H2S含量明显高于、而SPAP明显低于假手术组(P<0.05)；分流+NaHS组大鼠血浆ET-1含量及肺组织ET-1mRNA的表达明显低于分流组(P<0.05)；分流+NaHS组大鼠肺动脉CTGF蛋白表达明显低于分流组(P<0.05)。结论: NaHS可能通过降低血管活性肽ET-1 及CTGF在肺组织的表达参与调节高肺血流性肺动脉高压的形成。     

骨髓干细胞动员与移植治疗心肌梗死的比较

目的：比较骨髓干细胞动员与骨髓单个核细胞移植对兔心肌梗死的治疗作用，探讨更有效、更适用的干细胞治疗心肌梗死的方法。 方法： 将30只新西兰兔采用结扎前降支的方法复制心肌梗死模型，随机分为动员组、移植组和对照组，动员组（n=10）心梗后3 h开始皮下注射粒细胞集落刺激因子（G-CSF）30 μg·kg-1·d-1，连续使用5 d，第5 d抽取静脉血约10 mL，分离单个核细胞(BMCs)用5-溴脱氧尿嘧啶核苷（BrdU）标记后，经静脉注入动物体内。移植组（n=10）心梗后7-10 d，抽取骨髓3-5 mL,分离MNCs用BrdU标记，然后开胸将细胞移植至梗死区，对照组（n=10）不采取任何治疗措施。心梗后1周及5周采用超声心动图（UCG）检查心脏功能变化，5周时作血液动力学测定，取心脏作免疫组织化学鉴定。 结果： 心梗后5周，动员组左室射血分数（EF）明显高于1周时，移植组无变化，对照组显著下降。5周时动员组及移植组左室舒张末压（LVEDP）、+dp/dtmax和-dp/dtmax与对照组相比均有显著差异。动员组及移植组在心肌梗死区均发现有BrdU标记的阳性细胞，两组梗塞区血管密度明显高于对照组，但均未发现有新生的平滑肌细胞及心肌细胞。 结论： 骨髓干细胞动员及BMCs移植治疗心肌梗死，均能通过促进梗死区血管新生，明显改善心脏功能，骨髓干细胞动员可能为心肌梗死的治疗提供一种新的无创性手段。     

阿托伐他汀对糖尿病大鼠急性心肌梗死后心功能及HGF/c-Met信号通路的影响*

 目的： 糖尿病患者急性心肌梗死（AMI）后的心室重构及心功能恶化较非糖尿病者更为明显。本研究旨在观察阿托伐他汀对糖尿病大鼠AMI后心肌细胞凋亡、心室重构及心功能的影响,并探讨其作用是否与肝细胞生长因子及其受体 (HGF/c-Met)信号通路有关。方法: 70只雄性SD大鼠经链脲霉素 (STZ, 65 mg/kg)腹腔注射,诱导糖尿病大鼠模型。8周后对糖尿病大鼠结扎左冠状动脉前降支构建AMI大鼠模型,术后存活32只大鼠随机分为2组：AMI对照组(n=16)和阿托伐他汀干预组(n=16, 阿托伐他汀20 mg·kg-1·d-1),并在糖尿病大鼠中设假手术组(n=11),术后24 h予以灌胃给药。2周后比较各组大鼠心功能、心肌组织病理改变、心肌细胞凋亡、HGF和c-Met mRNA及蛋白表达差异。结果: (1) AMI对照组心功能显著低于假手术组（P<0.05）,胶原容积分数、心肌细胞凋亡指数、HGF及c-Met mRNA及蛋白表达均显著高于假手术组（P<0.05）;(2) 阿托伐他汀干预组的胶原容积分数和心肌细胞凋亡指数显著低于AMI对照组（P<0.05）,心功能、HGF及c-Met mRNA及蛋白表达均显著高于AMI对照组（P<0.05）。结论: 阿托伐他汀对糖尿病大鼠AMI后心肌细胞凋亡、心室重构及心功能具有显著改善作用;HGF/c-Met信号通路在AMI后会激活,阿托伐他汀的上述作用机制可能与其进一步增强HGF/c-Met信号通路有关。     

阿托伐他汀对心肌梗死大鼠心肌细胞核内FoxO3a表达的影响

目的探讨阿托伐他汀对大鼠心肌梗死(myocardial infarction,MI)后心肌细胞核内FoxO3a表达和心室重构的影响。方法建立大鼠MI模型,24 h后存活大鼠随机分成MI组(n=8)、阿托伐他汀10 mg组[10 mg/(kg.d),Ato组,n=8],同时另设假手术组(Sham组,n=10)。4周后观察左心室质量指数(left ventricular mass index,LVMI),免疫组化染色和RT-PCR检测FoxO3a在左心室非梗死区(non-infarction zone,NIZ)心肌细胞核内蛋白质和mRNA表达水平,流式细胞技术(flow cytometry,FCM)检测FoxO3a蛋白在NIZ心肌细胞核内表达含量。SAS9.1统计软件分析数据。结果 MI组与Sham组相比,LVMI显著增加(P<0.05);左室心肌非梗死区FoxO3a mRNA、FoxO3a蛋白表达(免疫组化)、FCM检测心肌细胞核内蛋白表达量表达均降低(P<0.05)。与MI组相比,Ato组LVMI显著下降(P<0.05);但高于Sham组(P<0.05);与MI组比较Ato组左室心肌非梗死区FoxO3a mRNA、Fox-O3a蛋白表达(免疫组化)、FCM检测心肌细胞核内蛋白表达量表达均显著增高(P<0.05);但低于Sham组(P<0.05)。结论阿托伐他汀能够有效地改善MI后心室重构,机制可能与上调细胞核内FoxO3a表达量有关。     

卡维地洛、西拉普利及其合用防治大鼠急性心肌梗死左室重塑的作用

目的:评价卡维地洛、西拉普利及其合用防治大鼠急性心肌梗死(AMI)左室重塑(LVRM)的作用。方法:AMI术后24h存活的100只雌性SD大鼠随机分成:①AMI对照(n=25)、②AMI+卡维地洛(1mg·kg^-1·d^-1, n=25)、③AMI+西拉普利(1mg·kg^-1·d^-1, n=25)及④AMI+合用(n=25)4组;另设假手术组(n=17).直接灌胃给药。4周后行血流动力学测定和病理学分析。去除梗死面积<35%或>55%者, 最终在以上各组分别有(13, 12, 12, 14)和13只大鼠。结果:AMI各组间梗死面积差异均无显著性(45.2%-46.7%, 均P>0.05).AMI对照组的左室舒张末压(LVEDP)、容积(LVV)、重量(LVW)和室间隔厚度(STh)均显著大于假手术组(均P<0.01), 左室内压最大上升和下降速率(±dp/dt)及其校正值(±dp/dt/LVSP)均显著低于假手术组(P<0.05, P<0.01).卡维地洛、西拉普利及合用组的LVEDP、LVV均显著低于AMI对照组(P<0.01), STh均显著薄于AMI对照组(P<0.01), LVW均显著轻于AMI对照组(P<0.05, P<0.01), ±dp/dt显著高于AMI对照组(P<0.05, P<0.01), 且LVEDP和STh在合用组显著低于两单用药组(P<0.05, P<0.01), 余指标在3个用药组间差异均无显著性(均P>0.05).结论:卡维地洛、西拉普利及其合用均能有效防治大鼠AMI左室重塑并改善血流动力学和左室功能,且以合用更佳。     

Toll样受体3在自身免疫性心肌炎小鼠心肌组织中的表达及意义

目的： 探讨实验性自身免疫性心肌炎BALB/c小鼠模型心肌组织中Toll样受体3的表达变化及意义。方法：用猪心肌肌球蛋白诱导建立BALB/c小鼠自身免疫性心肌炎模型,心肌炎模型组(n=20)和poly(I∶C)干预组(n=24)小鼠于第0 d和7 d皮下注射猪心肌肌球蛋白和完全弗氏佐剂,对照组(n=18)小鼠相同时间仅注射完全弗氏佐剂。于初次免疫后的第14 d和21 d分别留取血清和心肌标本。HE染色光镜下观察心肌组织的炎症情况,间接ELISA法检测小鼠血清中抗肌球蛋白IgG抗体,采用免疫组织化学和实时-PCR检测心肌组织中Toll样受体3蛋白和mRNA的表达变化。结果：光镜下表现和血清学指标均提示心肌炎症;免疫组织化学显示Toll样受体3在实验性自身免疫性心肌炎模型中有表达;在poly(I∶C)注射12 h后Toll样受体3 mRNA表达量最高,约为基础表达量的20倍,显著差异(P<0.05),且呈时间依赖性;心肌炎模型组中干扰素β和肿瘤坏死因子α mRNA表达与正常对照组比较分别增加14倍和18倍,显著差异(P<0.05)。结论：自身免疫性心肌炎小鼠心肌中Toll样受体3表达增加,其诱导的炎症反应与Toll样受体3介导的信号转导通路有关。     

骨髓间充质干细胞自体移植治疗阿霉素心肌病

目的:探讨骨髓间充质干细胞(MSCs)自体移植入兔阿霉素(ADR)心肌病心肌后的微环境依赖性分化及对心功能的影响。方法:日本大耳白兔随机分为:心肌病自体细胞移植组(n=10),心肌病对照组(n=8)及假手术组(n=6)。将自体MSCs和同体积的培养基分别移植入前两组动物心肌内,假手术组仅作开胸术而无移植。术后4周行心功能及组织学检测。结果:与假手术组相比,心肌病组的心功能明显降低;与心肌病对照组相比,自体移植组的心功能有显著改善,并在移植部位发现移植细胞有心肌肌钙蛋白T的表达。结论:MSCs移植入ADR心肌病的心肌组织中后,可在其微环境中存活并分化为心肌样细胞,并显著改善左室功能。     

双特异抗体增效内皮祖细胞移植促进心肌血管新生

目的探讨在双特异抗体(BiAb)的辅助下,内皮祖细胞(EPCs)移植可否更好的定向归巢大鼠缺血心肌促进血管新生。方法体外分离培养鉴定SD大鼠骨髓源性内皮祖细胞;开胸结扎SD大鼠冠状动脉左前降支制备心肌梗死模型;以anti-CD34(能识别内皮祖细胞)和抗肌凝蛋白轻链抗体(AMLCA)(能特异性结合缺血心肌)2种抗体,化学交联法制备BiAb(CD34×AMLCA)。将此BiAb与EPCs经尾静脉输入心肌梗死大鼠(EPCs+BiAb组),另设单纯EPCs移植组、单纯BiAb组、对照组。细胞移植35 d后M型超声心动图检测大鼠左室收缩功能,免疫组织化学法行5-Brdu及VIII因子检测,实时荧光定量PCR及Western blot检测大鼠心肌VEGF mRNA与蛋白表达。结果与其余组相比,EPCs+BiAb组射血分数及短轴缩短率增加,心梗区周围5-BrdU阳性细胞数及微血管密度增加,心肌VEGF mRNA与蛋白表达增加(P<0.05)。结论 CD34×AMLCA双特异抗体可增效大鼠骨髓源性内皮祖细胞定向归巢到大鼠缺血心肌,改善心功能,更好的促进血管新生。     

Controlled release of stromal cell-derived factor-1 alpha in situ increases c-kit+ cell homing to the infarcted heart

Stromal-derived factor 1alpha (SDF-1alpha) is a key stem cell homing factor that is crucial for mobilization of stem cells from bone marrow to peripheral blood and subsequent engraftment to the tissue of diseased organs. It has been reported that SDF-1alpha is transiently over-expressed in ischemic myocardium. Therefore, there may be a limited time window after acute myocardial infarction (AMI) during which stem cells are recruited to injured myocardium for repair. This study aimed at investigating whether controlled release of SDF-1alpha via a novel conjugated poly(ethylene glycol) (PEG) (PEGylated) fibrin patch at the infarct site would increase the rate of stem cell recruitment and offer potential therapeutic benefits. Recombinant mouse SDF-1alpha was covalently bound to the PEGylated fibrinogen as evidenced by immunoprecipitation and western blotting. The PEGylated fibrinogen, bound with recombinant mouse SDF-1alpha, was mixed with thrombin to form the PEGylated fibrin patch. The release kinetics of SDF-1alpha were detected in vitro using enzyme-linked immunosorbent assay. Using a mouse AMI model produced by a ligature on the left anterior descending coronary artery, a PEGylated fibrin patch bound with SDF-1alpha (100 ng) was placed on the surface of the infarct area of the left ventricle. Infarct size, left ventricular (LV) function, and the percentage of sca-1(+)/c-kit(+) cells within the infarct area were measured at days 7, 14, and 28 after AMI. In vitro results showed that SDF-1alpha was successfully bound to the PEGylated fibrin patch and can be released from the patch constantly for up to 10 days. Two weeks after infarction, the myocardial recruitment of c-kit(+) cells was significantly higher in the group treated with the SDF-1alpha PEGylated fibrin patch (n = 9) than in the AMI control group (n = 10) (p < 0.05; 11.20 +/- 1.71% vs. 4.22 +/- 0.96%, respectively). At day 28 post-AMI, unlike the control group, the group with the SDF-1alpha-releasing patch maintained stable release of SDF-1alpha concurrent with additional stem cell homing. Moreover, LV function was significantly better than in the control group. These data demonstrate that the PEGylated fibrin patch based SDF-1alpha delivery can improve the rate of c-kit(+) cell homing and improve LV function in hearts with postinfarction LV remodeling.     

The postsubiculum is necessary for spatial alternation but not for homing by path integration

The postsubiculum is a structure of interest because it projects to the hippocampal formation and contains head direction cells, grid cells, and border cells. The aim of the current experiment was to test whether the postsubiculum is necessary for homing by path integration. Rats were trained on a homing task on a large circular platform. After exhibiting stable homing, one group of animals (n = 6) received ibotenic acid lesions of the postsubiculum, and a second (n = 5) underwent a control surgery. After recovery, animals with postsubiculum lesions homed as accurately as the control animals. Subsequent testing on a delayed alternation T maze task showed that the lesioned animals were significantly worse than the control animals at delays of 5-, 30-, and 60-s. These findings suggest that the postsubiculum is necessary for memory and avoidance of previously visited locations but is not necessary for homing.     

血管内皮生长因子基因转染骨髓间充质干细胞同种异体移植治疗大鼠急性心肌梗死

目的探讨同种异体血管内皮生长因子(VEGF)基因转染的骨髓间充质干细胞(MSCs)在大鼠梗死心脏局部存活、分化及对心功能的影响;明确同种异体干细胞及VEGF基因转染干细胞移植治疗急性心肌梗死(AMI)的可行性及效果。方法雄性SD大鼠30只,随机分为单纯注射培养基对照组、MSCs治疗组及VEGF基因转染MSCs治疗组。分离纯化雄性Wistar大鼠骨髓间充质干细胞(rMSCs),于左冠状动脉前降支结扎1h后植入到SD大鼠心组织,移植4周后检测心功能并取心脏行组织染色检查。结果异体大鼠MSCs可在梗死心组织定居、生存;免疫组化检测MSCs转化为心肌细胞及血管内皮细胞;与对照组比较VEGF基因转染异体细胞移植组左室射血分数升高(P<0.05),梗死边缘区心肌面毛细血管数目明显增加(P<0.05)。结论同种异体VEGF基因转染MSCs移植治疗AMI可行、有效。     

c-kit与miR-21在心衰大鼠心肌中表达下降

目的研究c-kit与miR-21基因在大鼠左室重构中的动态表达及其作用机制。方法将大鼠140只随机分为正常对照组15只和心衰模型组125只。心衰模型制作:4 mg/kg腹腔注射阿霉素。在8周时对大鼠进行心功能检测,验证心衰模型。取心脏组织冰冻切片。利用免疫组化及免疫荧光显色等技术检测心肌组织中miR-21和c-kit的基因表达。结果 1)心衰组的呈现心肌梗死后心肌细胞的病理学变化。2)在正常和心衰心肌中miR-21阳性细胞主要表达于血管内皮,少量心肌细胞和干细胞,而心衰心肌组织中的表达量明显减少;c-kit阳性细胞常成群分布,主要聚集于心外膜及其附近。在两组心肌组织中均有少数细胞存在miR-21和c-kit共表达。结论 c-kit和miR-21在心衰大鼠心肌中表达下降与心力衰竭和左室重构呈高度相关。     

The expression of stem cell factor and c-kit receptor in human asthmatic airways

BACKGROUND: Asthmatic airways are characterized by infiltration with a variety of inflammatory cells such as mast cells and eosinophils. Stem cell factor (SCF) is an important activating and chemotactic factor for both mast cells and eosinophils. In addition, it is a critical growth and differentiation factor for mast cells. OBJECTIVES: To investigate the contribution of SCF to the pathogenesis of asthma, we examined the expression of SCF and its receptor c-kit in bronchial biopsies and bronchoalveolar lavage (BAL) specimens obtained from asthmatic subjects (n=13) and non-asthmatic control subjects (n=10). METHODS: SCF and c-kit were detected by in situ hybridization (ISH) and immunocytochemistry (ICC). In order to phenotype the cells expressing SCF and c-kit in asthmatic tissue and BAL cells, combined ISH and ICC were also performed. RESULTS: There was a significant difference (P<0.001) in the SCF mRNA expression in asthmatic airway epithelium (70.38+/-12.33% positive cells) compared with controls (12.7+/-17.21% positive cells). There was also a significant difference in subepithelial SCF-mRNA expression, being higher in asthmatics (P<0.001). A significant difference was also found in c-kit receptor mRNA expression in asthmatic biopsies both in epithelium (P<0.001) and subepithelium (P<0.05) compared with controls. ICC results were consistent with the ISH for both SCF and c-kit receptor from asthmatics and controls. The SCF and c-kit receptor mRNA and immunoreactivity in cells recovered from bronchial washing were also significantly higher in asthmatics compared with controls (P<0.05). While SCF expression was localized predominantly in the epithelial layer in bronchial biopsy tissues, alveolar macrophages were found to be the major source of SCF in bronchial washing from asthmatic subjects. CONCLUSION: The results of this study demonstrate the increased expression of SCF and its receptor, c-kit within human asthmatic airways, which suggests an important role of this cytokine in the pathophysiology of asthma.     

Therapeutic effect of human umbilical cord-derived mesenchymal stem cells in rat severe acute pancreatitis

Aim: To investigate the therapeutic effect of umbilical cord-derived mesenchymal stem cells (UC-MSCs) on rat severe acute pancreatitis (SAP). Methods: Rats were randomly divided into three groups (n = 15 per group): control group, SAP group, and SAP+MSCs group. SAP was established by retrograde pancreatic duct injection of 3% sodium taurocholate. In SAP+MSCs group, UC-MSCs at 1×10⁷ cells/kg were injected via the tail vein 12 h after SAP. Rats (n = 5 per group) were sacrificed on days 1, 3 and 5, and the blood and pancreatic tissues were collected. The levels of serum amylase, lipase, inflammatory cytokines, and anti-inflammatory cytokines were determined. Pathological changes of the pancreas (HE staining) and apoptotic acinar cells (TUNEL staining) were observed under light microscope. Results: The levels of serum amylase and lipase in SAP group were significantly higher than those in control group (P<0.05). The pancreas in SAP group showed significantly massive edema, inflammation, hemorrhage and necrosis when compared with control group. There were numerous TUNEL-positive apoptotic acinar cells after SAP. However, in SAP+MSCs group, the levels of serum amylase were significantly reduced on days 1, 3, and 5 after MSC transplantation (P<0.01). The serum lipase level in SAP+MSCs group was significantly lower than that in SAP group on days 3 and 5 (P<0.01). The edema formation, inflammatory cell infiltration, hemorrhage, and necrosis were reduced significantly attenuated in SAP+MSCs group as compared to SAP group (P<0.05). MSCs significantly reduced the levels of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), but increased the levels of anti-inflammatory cytokines (IL-4 and IL-10) in SAP rats. The number of TUNEL-positive acinar cells was significantly reduced on days 3 and 5 after MSCs transplantation (P<0.01). Conclusion: Transplantation of UC-MSCs significantly inhibits inflammation and decreases pancreatic injury secondary to SAP.     

豚鼠糖尿病性膀胱病逼尿肌中c-kit mRNA和蛋白的表达变化及意义

目的: 检测豚鼠糖尿病性膀胱病(DCP)逼尿肌中酪氨酸蛋白激酶生长因子受体(c-kit)mRNA和蛋白的表达水平,探讨c-kit表达与DCP的关系及其发病机制。方法: 60只豚鼠随机分成对照组20只,实验组40只,实验组采用链脲佐菌素(STZ)建立糖尿病豚鼠模型,2组豚鼠饲养10周后运用尿动力学检测并将实验组筛选出DCP组和糖尿病性非膀胱病(NDCP)组,应用RT-PCR、激光共聚焦显微镜技术分别检测各组膀胱组织c-kit mRNA和蛋白的表达。结果: DCP组c-kit mRNA表达显著低于对照组(P<0.01)及NDCP组(P<0.05),相对平均吸光度值分别为4.65±0.47、5.66±0.54、5.54±1.28。糖尿病性膀胱病组c-kit蛋白表达明显低于对照组(P<0.01)与NDCP组(P<0.01),c-kit蛋白荧光值分别为548.69±48.51、844.67±59.24、856.52±53.03。结论: 豚鼠DCP逼尿肌中c-kit mRNA、c-kit蛋白表达减少,导致c-kit信号通路异常,从而使Cajal样细胞在膀胱中的功能减弱而导致逼尿肌功能障碍发生DCP,因此c-kit表达异常可能是DCP的发病机制之一。     

Gln和rhGH对门脉高压症术后肠粘膜屏障及增殖细胞核抗原表达的影响

目的：研究单独或联合应用谷氨酰胺（Gln）和重组人生长激素（rhGH）对门脉高压症术后肠粘膜屏障功能的保护作用及机制。方法:29例门静脉高压症术后患者随机分为4组：①Gln组（n=6），②rhGH组（n=8），③Gln+rhGH组（n=7）和④对照组（n=8）。术后3 d开始进行等氮、等热量的全胃肠外营养支持（TPN），持续7 d。对手术前、后的尿乳果糖排泄率/甘露醇排泄率（L/M）、十二指肠粘膜绒毛高度、陷窝深度及肠粘膜增殖细胞核抗原（PCNA）表达指数进行对比。结果:Gln+rhGH组术后L/M值升高小于对照组（P<0.05），肠粘膜绒毛高度和陷窝深度大于对照组（P<0.05）及术前（P<0.05），肠粘膜上皮PCNA表达指数大于术前及其它3组（P<0.05）；对照组术后绒毛高度小于术前（P<0.05），陷窝深度变化无显著（P＞0.05）。结论：联合应用Gln和rhGH能降低门脉高压症术后肠壁通透性并维护肠粘膜形态学完整性，单用Gln或rhGH无此作用。这种作用可能与增加肠黏膜PCNA表达而促进肠黏膜上皮细胞增殖有关。     

含人AGM区基质细胞培养体系定向诱导胚胎干细胞为造血干细胞的实验研究

目的： 体外模拟胚胎早期AGM区造血微环境，诱导胚胎干细胞（ESCs）分化为造血干细胞（HSCs）。方法：将小鼠E14 ESCs在含BMP-4及VEGF的半固体培养基中诱导为拟胚体（EB），分别于3、6、9、12、15 d时收获EB，流式细胞术检测Flk-1+细胞含量。取Flk-1+ 细胞处于高峰期的EB细胞，在人AGM区基质细胞饲养层上进一步诱导分化，并设无饲养层对照，分别于3、6、9、12 d时收获细胞计数、流式细胞术检测Sca-1+c-kit+ 细胞含量，并分析造血细胞集落形成能力。结果：诱导E14细胞形成EB过程中添加BMP4+VEGF的因子组Flk-1+细胞在第9 d达峰值（27.53%± 2.84％），与未添加因子组（8.77%± 1.12％）比较差异显著(P<0.05)。将培养9 d的EB细胞在hAGMS3、hAGMS4饲养层上进一步诱导分化，第6 d时Sca-1+c-kit+细胞达峰值，分别为7.31%±1.21％、7.62%±1.52％，其绝对数分别扩增(2.57±0.48)倍、(2.35±0.36)倍，与无饲养层组比较显著差异（P<0.05）。该分化阶段的Sca-1+c-kit+细胞具有形成各系造血细胞集落的能力。结论：人胚早期AGM区基质细胞能促进小鼠ESCs定向分化为HSCs，为研究ESCs分化为HSCs的分子机制提供了实验模型。     

NF-κB在发育鼠戊四氮反复点燃癫痫形成中的作用

目的：用NF-κB阻滞剂吡咯烷二硫基甲酸盐(PDTC)阻断NF-κB的表达，探讨核因子κB(NF-κB)在发育鼠戊四氮(PTZ)点燃癫痫形成过程中的作用。方法:生后10 d（P10）Wistar大鼠72只，随机分为PTZ组、PDTC＋PTZ组及生理盐水对照组3组，制备戊四氮反复点燃癫痫模型。观察各组大鼠行为学改变、海马各区细胞形态及细胞计数、NF-κB表达、5-溴-2-脱氧尿嘧啶核苷(BrdU)阳性细胞数和苔藓纤维发芽等指标。结果:(1)NF-κB表达，PTZ组显著高于对照组及PDTC+PTZ组（P<0.01）；(2)海马神经细胞计数，PTZ组齿状回（DG）区颗粒细胞较对照组显著增加(P<0.05)；PDTC+PTZ组CA1、CA3和门区神经元数较PTZ组均明显减少（P<0.05）；(3)DG区BrdU阳性细胞数，PTZ组和PDTC+PTZ组均较对照组显著增加（P<0.01）；PDTC＋PTZ组DG区BrdU阳性细胞数目明显较PTZ组少（P<0.01）；NF-κB吸光度值与BrdU阳性细胞数/颗粒细胞数相关性分析呈正相关，具有统计学意义（P<0.01）；（4）苔藓纤维发芽，PDTC＋PTZ组和PTZ组均有苔藓纤维发芽，两组比较没有显著差异。结论:NF-κB在发育鼠癫痫中发挥重要作用，促进海马神经元发生，保护海马神经细胞，但对苔藓纤维发芽无明显作用。