血管生长素基因转染5-氮胞苷诱导后的骨髓基质细胞移植于缺血心肌的实验研究

目的　利用编码血管生长素基因的腺病毒 (Ad .ANG)转染 5 氮胞苷 (5 aza)诱导骨髓基质细胞 (BMSC) ,移植于大鼠缺血心肌后对心功能的保护和促血管新生作用。方法　体外培养Lewis大鼠的骨髓基质细胞 ,使用 3μmol/L的 5 aza体外强化诱导 2 4h ;然后在 5 0倍的转染倍数 (病毒数 /靶细胞 )下 ,用Ad .ANG转染诱导BMSC。通过ELISA方法检测其对ANG的表达和分泌。然后将其移植于结扎了冠状动脉前降支的Lewis大鼠缺血心肌内 (组Ⅰ )。同时设置单纯细胞移植组 (组Ⅱ )和基因治疗组 (组Ⅲ ) ,以注射无血清培养基的实验动物为对照组 (组Ⅳ )。通过心脏射血分数 (EF)、左室舒张末期容积等超声指标研究其对心功能的保护作用 ;另外通过免疫组化、电镜研究细胞存活、分化和血管新生情况。结果　Ad ANG转染BMSC后 ,在培养上清中ANG大量出现 ,4～ 7d时达到表达高峰 ,15d后仍可检测到蛋白质表达。移植于缺血心肌 4周后 ,组Ⅰ和组Ⅱ缺血区的移植细胞大部分分化为心肌样细胞 ,组ⅠEF改善程度明显好于组Ⅱ (P <0 0 5 )、组Ⅲ (P <0 0 1)和组Ⅳ (P <0 0 1) ,在促血管新生方面 ,组Ⅰ也明显优于以上 3组 (组Ⅰ 36 3个 /HPF ;组Ⅱ 10 5个 /HPF ;组Ⅲ 2 3 1个 /HPF ;组Ⅳ 0 9个 /HPF)。结论　转染Ad ANG后的BMSC移植于缺     

纳米粒子介导血管内皮生长因子基因治疗兔心肌缺血的疗效

目的观察纳米粒子介导血管内皮生长因子(VEGF)基因转染的可行性,了解心肌缺血动物模型经心肌直接注射VEGF基因纳米粒子后新生血管以及心功能改善情况。方法应用聚乳酸聚乙醇酸共聚物(PLGA)和聚乙烯醇(PVA)包载VEGF165基因质粒,制备纳米级粒子混合物,检测其载药量、体外释放情况及粒径;培养乳鼠心肌细胞,转染VEGF165基因纳米粒子(VEGF纳米粒子),应用RT-PCR法检测VEGF mRNA水平,ELISA法检测VEGF蛋白表达水平;将VEGF纳米粒子悬浮液注射至活体家兔心肌内,96h后心肌注射部位取材,电镜观察其向心肌组织内传递基因的可行性;建造兔心肌缺血模型,分别将VEGF纳米粒子(12只)、VEGF165裸质粒(12只)或生理盐水(对照组,8只)注射至缺血部位心肌,1个月后心脏超声监测,然后处死,组织学切片观察心肌组织中毛细血管生成情况。结果制备的纳米粒子载药量为1·87%,粒径为50~300nm;RT-PCR和ELISA结果提示纳米粒子可将目的基因转移至培养的心肌细胞中;体内实验显示心肌细胞胞质内及胞核内可见大量被吞噬的纳米粒子;术后1个月超声检查显示,VEGF纳米粒子组室壁运动幅度(1·87mm±0·32mm)、左室射血分数(60%±10%)较裸质粒组(1·59mm±0·24mm,50%±6%)及对照组(0·93mm±0·40mm,40%±8%)改善更加明显,各组之间差异均有统计学意义(均P<0·05);组织学检查显示,在100倍光镜视野下心肌内毛细血管数VEGF纳米粒子组(57个±12个)明显高于裸质粒组(41个±14个)及对照组(24个±8个),各组之间差异有统计学意义(均P<0·05)。结论纳米粒子可作为VEGF基因向心肌组织转运的载体,在兔心肌缺血模型经心肌直接注射VEGF165基因纳米粒子,能够促进心肌内毛细血管新生,达到改善心功能的目的。     

结扎冠状动脉不同分支建立兔心肌梗死模型的效益比较

目的:研究无呼吸机辅助下正中开胸表面结扎兔左冠状动脉不同分支建立心肌梗死模型的成功率、建模效果以及二次开胸存活率。方法:25只兔随机取1只作为健康对照,其余平均分为前降支组和左室支组;两组均行表面结扎冠状动脉建立心肌梗死模型。分别于建模前后行心电图和心脏彩超检查。建模成功后4周末二次开胸,2周后处死动物,留取心脏组织观察病理变化。结果:两组动物建模存活率无差别;以心电图出现ST段动态变化和4周后病理性Q波形成,结合心脏彩超左室缩短分数显著降低(P<0.05)为建模成功标准,左室支组建模的成功率略高于前降支组,但建模成功后的效果两组无明显差别(P>0.05);二次开胸左室支组存活率明显高于前降支组。结论:表面结扎兔冠状动脉左前降支和左室支均能成功建立心肌梗死模型,建模效果无明显差别;结扎左室支时二次开胸存活率明显高于结扎前降支,其更适用于需要多次进行心脏表面操作的实验。     

碱性成纤维生长因子对急性心肌梗死血管生成和碱性成纤维生长因子及血管内皮生长因子表达的作用

目的探讨心肌内注射碱性成纤维生长因子(bFGF)对急性心肌梗死(MI)血管生成和bFGF、血管内皮生长因子(VEGF)表达的作用。方法24只犬建立急性MI模型后随机分成对照组(MI区注射生理盐水15ml)和实验组(MI区注射50mg bFGF与生理盐水的混合液15ml)。每组观察4个不同的时间点(术后第1天、第3天、第10天、第17天)。各组分别在处死前应用敏感编码技术行磁共振电影成像。免疫组织化学方法检测各组心肌细胞中bFGF和VEGF的表达及微血管数量。结果实验组左心室射血分数自第10天明显增加;除第1天外各个时间点的微血管数量实验组比对照组明显增多;心肌缺血区对照组bFGF和VEGF的表达增多。结论局部心肌内注射bFGF有促进MI区域毛细血管形成及提高左心室功能的作用。     

碱性成纤维细胞生长因子诱导大鼠缺血心肌血管新生的作用

目的　探讨局部应用碱性成纤维细胞生长因子(bFGF)对大鼠急、慢性缺血心肌血管新生的作用。　方法　健康雄性Wistar大鼠,采用开胸结扎左冠状动脉前降支法制备急、慢性心肌梗死模型,并随机分为bFGF组和对照组(n =8) ,bFGF组以0 .0 2mL(2 0 μg/kg ,0 .2 5mg/mL)造模时或造模1个月后于结扎处局部注射,对照组以等容积生现盐水处理。注射后1个月观察血流动力学参数、心肌梗死面积和侧支微血管数目的变化。　结果　bFGF组心率、左室舒张末压明显低于对照组(P <0 .0 1)、平均动脉压、左室收缩压、左室最大收缩速率明显高于对照组(P <0 .0 1) ;bFGF组心肌微血管数明显多于对照组(P <0 .0 1) ;急性心肌梗死模型bFGF组心肌梗死面积明显小于对照组(P <0 .0 1) ,慢性心肌梗死模型bFGF组心肌梗死面积与对照组比较差异无显著性(P >0 .0 5 )。　结论　局部应用bFGF能明显促进缺血心肌血管新生,缩小急性心肌梗死面积,改善血流动力学。     

结扎冠状动脉建立急性心肌梗塞动物模型的改进

麻醉兔结扎冠状动脉造成急性心肌梗塞模型。实验动物分成两组。对照组,结扎左冠脉前降支的第一分支;改进组,于左冠脉前降支第一分支下及左室支下降段1/2处结扎冠脉。动态观察并记录体表心电图变化。结果改进组与对照组各时间的△ST及Σ△ST段相比均有显著性差异(P<0.05和P<0.01,n=9)。将存活6h的兔处死并取心室作N-BT大体染色,计算梗塞区占心室重的百分比以判断梗塞范围。结果表明,改进组心室梗塞平均百分比为24.7%,对照组为6.7%。提示:改进的急性心肌梗塞模型,不仅避免了只结扎冠脉前降支后代偿性侧枝循环的迅速建立给实验带来的影响;还避免了高位结扎冠脉前降支造成血压迅速下降甚至死亡的危险,是一种有参考价值的方法。     

慢性低氧性肺动脉高压大鼠血清碱性成纤维细胞生长因子含量的 …

为探讨碱性成纤维细胞生长因子在慢性低氧性肺动脉高压肺血管重建中的作用及机理，采用慢性低氧性肺动脉高压大鼠模型，用酶联免疫吸附法测定其血清ｂＦＧＦ含量，并用原位杂交法观察肺、心、脑、肾等器官ｂＦＧＦｍＲＮＡ表达的变化。     

混合细胞共微囊化对肝细胞功能的支持作用

目的观察大鼠肝细胞、转基因肝星状细胞株HGF／CFSC和／或大鼠骨髓来源Thy-1^＋β2M^-细胞（BDTC）共微囊化对肝细胞生物学活性的支持,及腹腔移植混合细胞微囊对急性肝衰竭大鼠肝功能的改善作用。方法利用微囊发生器制备含肝细胞或混合细胞的微囊,依微囊内包裹细胞种类不同,分为微囊化肝细胞组、微囊化肝细胞＋CFSC／HGF组）和微囊化肝细胞＋CFSC／HGF＋BDTC组,通过观察囊内细胞形态和体外培养测定培养液中白蛋白和尿素的分泌,判断各组囊内肝细胞活性和功能的维持;将90％肝大部切除所致的急性肝衰竭大鼠按照移植微囊种类不同分为空囊对照组和上述3个实验组（每组10只）,观察腹腔植入后不同时间大鼠的一般状况、存活时间、血生化改变、肝组织再生及微囊化移植物的组织学特征。结果与单独肝细胞微囊者相比,混合细胞微囊内肝细胞存活时间超过1倍,培养液中白蛋白分泌和尿素合成量明显增加（均P〈0．01）;与对照组相比,微囊化肝细胞或微囊化混合肝细胞移植后,急性肝衰竭大鼠的肝功能显著改善、存活率明显提高（10／10 vs 1／10）,其肝组织再生完全;移植21—42d时,部分微囊附着于肝脏表面并出现血管化,微囊表面存在不同程度的纤维化,微囊内仍有存活的细胞,以微囊化混合肝细胞组优于微囊化肝细胞组。结论混合细胞共微囊化能明显改善囊内肝细胞的存活寿命、形态和功能的维持,微囊化混合肝细胞腹腔移植对促进急性肝衰竭大鼠的肝功能恢复具有显著作用。     

血管紧张素Ⅱ调节大鼠心肌胶原的表达

目的观察血管紧张素Ⅱ(AngⅡ)对大鼠心肌Ⅰ、Ⅲ型胶原纤维蛋白基因表达的影响,评价DMP811(新型血管紧张素Ⅱ1型受体拮抗剂)对其干预作用.方法6周龄雄性SD大鼠随机分为3组,每组6只.(1)组生理盐水输注;(2)组AngⅡ输注;(3)组AngⅡ输注 DMP811管饲(3mg@kg-1@d-).1周后取其心脏,采用逆转录多聚酶链反应(RT-PCR)及胶原染色的方法分别检测心肌Ⅰ、Ⅲ型胶原基因的mRNA及蛋白表达水平.结果(2)组心重(CW)、心重/体重(C/B)、胶原Ⅰ、Ⅲ基因转录水平均高于(1)组,它们分别增加(4.7±0.4)%,(4.9±0.9)%,(22.0±4.7)%和(20.6±4.9)%(P＜0.01);而且心肌Ⅰ、Ⅲ型胶原蛋白沉积也较(1)组明显.AngⅡ导致的上述改变能被DMP811完全阻断.结论AngⅡ通过其1型受体的介导,上调心肌Ⅰ、Ⅲ型胶原基因的表达.     

血管再生治疗对急性心肌梗塞犬心脏功能的影响

目的 :采用超声心动图心功能测定、组织多普勒显像和血流多普勒频谱技术 ,评价心肌内控制释放碱性成纤维细胞生长因子 (bFGF)血管再生治疗对急性心肌梗塞 (AMI)犬心脏收缩与舒张功能的影响。方法 :18只成年健康杂种犬于开胸后结扎左前降支 (LAD) ,制作AMI模型。动物平均分为 3组 ,单纯心肌梗塞 (MI)组 ,直接关胸 ;激光心肌血运重建 (TMR)组 ,于AMI 30min后行透壁心肌打孔 ;bFGF组 ,于AMI 30min后行非透壁心肌打孔 ,并随后向孔道内注射含有bFGF的纤维蛋白胶 (FG) ,以封闭激光孔道。 8周后行超声心动图检查 ,以评价心脏收缩与舒张功能。结果 :MI组与TMR组于术后 2 2d和 34d各有一只死亡 ,bFGF组无死亡。bFGF组的左心室射血分数 (EF)、每搏出量 (SV)和心输出量 (CO)均明显高于MI组与TMR组 (P均 <0 .0 5 )。bFGF组的左心室面积变化分数 (FAC)明显高于MI组 ,室壁运动指数 (WMI)明显低于MI组 ,但与TMR组相比均无明显差异。尽管采用TMR和bFGF干预后有改善舒张功能的趋势 ,但采用二尖瓣口血流频谱和二尖瓣瓣环的组织多普勒血流显像两种方法测得 3组的E A比值却均无明显差异。结论 :使用FG在心肌内控制释放bFGF进行血管再生治疗安全可行 ,能显著改善急性心肌梗塞犬的收缩功能 ,但对梗塞心脏的舒张功能改善不明显?     

Transplanted human umbilical cord blood mononuclear cells improve left ventricular function through angiogenesis in myocardial infarction

Background Human umbilical cord blood contains an abundance of immature stem/progenitor cells, which may participate in the repair of hearts that have been damaged by myocardial infarction (MI). This study aimed to evaluate the effects of human umbilical cord blood mononuclear cells (hUCBC) transplantation on cardiac function and left ventricular remodeling in rat model of MI. Methods Forty-five male Wistar rats were randomized into three groups: MI or control group (n=15), MI plus cell transplantation (n=15), and sham group (n=15). Acute myocardial infarction (AMI) was established by ligating the left anterior descending artery, thereafter, hUCBC were implanted into the marginal area of infarcted myocardium. In MI/control group, DMEM was injected instead of hUCBC following the same protocol. Left ventricular function assessment was carried out by echocardiography and invasive hemodynamic measurements one month post MI. All rats were sacrificed for histological and immunochemical examinations. Results The transplanted hUCBC survived and engaged in the process of myocardial repair in the host heart. Echocardiography demonstrated that left ventricular function improved significantly in the rats that underwent cell transplantation. Hemodynamic studies found a significantly decreased left ventricular end-diastolic pressure (LVEDP) [(21.08±8.10) mmHg vs (30.82±9.59) mmHg, P&lt;0.05], increase in +dp/dt(max) [(4.29±1.27) mmHg/ms vs (3.24±0.75) mmHg/ms, P&lt;0.05), and increase in －dp/dt(max) [(3.71±0.79) mmHg/ms vs (3.00±0.49) mmHg/ms, P&lt;0.05] among MI group with hUCBC transplantation when compared with MI/control group. Masson’s trichrome staining revealed that the collagen density in the left ventricle was significantly lower in rats of transplantation group than that in the MI control groups [(6.33±2.69)% vs (11.10±3.75)%, P&lt; 0.01]. Based on immunostaining of α-actin, the numbers of microvessels were significantly (P&lt;0.01) increased at the boundary of infarction site. Similarly higher mRNA expression of vascular endothelial growth factor (VEGF) 164 and VEGF188 were found at 7- and 28-day post cell transplantation in MI group with hUCBC transplantation when compared with MI/ control group.Conclusions Transplanted hUCBC can survive in host myocardium without immunorejection, significantly improve left ventricular remodeling after AMI and promote a higher level of angiogenesis in the infarct zones. All these factors beneficially affect cardiac repair in the setting of MI. Therefore human umbilical cord blood may be potential source for cell-based therapy for AMI.     

Effects of nerve growth factor on delayed afterdepolarization and triggered activity in the infarcted ventricle of rabbit model

The noninfarcted myocardium underwent significant electrophysiological remodelling as part of the healed myocardial infarction remodelling.This study aimed at investigating the effects of nervous growth factor(NGF) on delayed afterdepolarizations(DADs) and triggered activity(TA) of the noninfarcted myocardium in the myocardial infarcted rabbit model.Rabbits with the left anterior descending coronary artery occlusion were prepared and recovered for 8 weeks(HMI group,n=9).Other rabbits with myocardial infa...     

Changes of Expressions of VEGF, bFGF, and Angiogenesis, and Effect of Benazepril, bFGF on Angiogenesis in Acute Myocardial Infarction Model of the Rabbits

Objective To explore the changes of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and angiogenesis, and the effects of bFGF, angiotensin converting enzyme inhibiter(ACEI) benazepril on the angiogenesis in acute myocardial infarction (AMI) model of rabbits, and to provide a probable evidence for the treatment of AMI. Methods AMI model was established by ligating anterior descending branch of coronary artery of Japan-Sino hybridization white rabbits. The postoperative rabbits were randomly divided into 6 groups and each group was treated with different drugs. Groups 1 and 2 were treated with normal saline (NS) for 28 and 14 days (d), group 3 and 4 with bFGF for 28 and 14 d, groups 5 with benazepril for 14 d, and group 6 with benazepril and bFGF for 14 d respectively. The rabbits were killed on the 14th or 28th d and their hearts were excised, sectioned and stained with HE, Masson trichrome to observe VEGF, bFGF and CD34 under a microscope, which were quantified with a computer-assisted morphometry. Results Compared with group 1, the granulation tissue of infarction zone (IZ) in group 2 freshened up, and the capillary density (CD) in IZ was increased (P=0.002). The CD in the IZ as well as VEGF and bFGF in groups 3 and 4 were increased respectively (P=0.011-0.037). In group 5 the changes of VEGF and bFGF were not found in the IZ and the border zone (BZ) while CD was significantly increased (35.4% and 25.6%, P=0.036 and 0.037). Compared with group 2, the CD in the IZ and BZ of group 6 was significantly increased (63.4% and 44.3% P=0,007 and 0.007), meanwhile VEGF and bFGF were increased. Compared with group 5, only VEGF was increased. Conclusion Intravenous bFGF may increase VEGF and bFGF significantly, thus promoting the angiogenesis in the IZ and BZ in cardiac infarction as VEGF and bFGF are the potent angiogenic growth factors. Benazepril may promote angiogenesis in the IZ and BZ in cardiac infarction, but its mechanism is irrelative to the expression of VEGF and bFGF. The combination of benazepril and bFGF may promote, to some extent, the expression of VEGF and bFGF, but their effect on angiogenesis has not been found.     

氯沙坦、卡托普利联合对兔心肌缺血再灌注诱导内皮细胞损伤的影响

目的:研究氯沙坦联合卡托普利对兔心肌缺血再灌注损伤内皮细胞的保护作用及其机制。方法:结扎兔左冠状动脉前降支制作心肌缺血再灌注损伤模型,随机分为空白对照组、缺血再灌注组和联合组。联合组在心肌缺血前10min给予氯沙坦和卡托普利。观察各组缺血再灌注过程中心电图的动态改变,以及氯沙坦和卡托普利联合对血管性血友病因子及丙二醛和血清一氧化氮含量、损伤兔血浆及心肌组织血管紧张素的水平的影响。结果:缺血再灌注组和联合组均造成明显的心电图动态改变,与空白对照组比较,联合组心电图ST段出现有效改变。缺血再灌注组和联合组血浆和心肌组织血管紧张素水平呈时间依赖性升高,血管性血友病因子活性和丙二醛水平较缺血再灌注组显著降低,而血清一氧化氮水平明显提高。结论:氯沙坦和卡托普利的联合使用对心肌缺血再灌注损伤内皮细胞有明显的保护作用,其作用与多层面的清除氧自由基的膜脂质过氧化及拮抗血管紧张素受体AT1有关。     

Na+/Ca2+ exchanger current and K+ current remodeling in midmyocardial cells of hypertrophic left ventricle]

OBJECTIVE: To investigate the characteristics of Na+/Ca2+ exchanger current (INa+ /Ca2+) and K+ current remodeling in midmyocardial cells of hypertrophic left ventricle for understanding the ionic basis of arrhythmia of the hypertrophic heart. METHODS: Twenty New Zealand rabbits were divided equally into normal control group and operation group, and in the latter, left ventricular hypertrophy was induced in the rabbits by partial ligation of the abdominal aorta. Action potentials, INa+/Ca2+, slowly activating delayed rectifier K+ current (IKs) and rapidly activating delayed rectifier K+ current (IKr) were recorded in the two groups by using whole-cell patch-clamp technique. RESULTS: At the basic cycle length of 2 s, 90% action potential duration (APD90) in control and operation groups was 522.0+/-19.5 ms (n=6) and 664.7+/-32.7 ms (n=7) respectively; at the testing potential of +40 mV, outward INa+/Ca2+ density in the two groups was 0.94+/-0.11 pA/pF (n=9) and 1.30+/-0.11 pA/pF (n=8) respectively; the testing potential of -100 mV elicited inward INa+/Ca2+ density of 0.40+/-0.05 pA/pF (n=9) and 0.56+/-0.02 pA/pF (n=8) respectively. The testing potential of +50 mV induced IKs tail current density of 0.26+/-0.03 pA/pF (n=8) and 0.17+/-0.01 pA/pF (n=9), and IKr tail current density of 0.34+/-0.02 pA/pF (n=8) and 0.23+/-0.02 pA/pF (n=9) respectively. Statistically significant differences were identified between the control and operation groups in all the above indices measured. CONCLUSION: The characteristics of electrical remodeling changes in midmyocardial cells of hypertrophic left ventricle, exhibited by prolonged action potential, up-regulated INa+/Ca2+ and down-regulated IKs and IKr.     

Electroanatomical systems to guided circumferential pulmonary veins ablation for atrial fibrillation: initial experience from comparison between the Ensite/NavX and CARTO system

Background The circumferential pulmonary vein ablation (CPVA) has been proved effective for atrial fibrillation (AF) treatment and is becoming more widely accepted and practiced. This study aims to evaluate the characteristics of the CARTO and the Ensite/NavX system and draw a comparison between them on the aspects of procedural parameters and clinical effectiveness.Methods Seventy-five cases with paroxysmal or chronic symptomatic AF were randomly assigned to CPVA procedure guided by the Ensite/NavX system (group Ⅰ, n=40) and by the CARTO system (group Ⅱ, n=35). After successful transseptal procedure, the geometry of left atrium was created under the guidance of the two systems. Radiofrequency energy was applied to circumferentially ablate tissues out of pulmonary veins’ (PVs’) ostia. In cases with chronic AF, linear ablation was applied to modify the substrate of left atrium （LA）. The endpoint of the procedure was complete PVs isolation. Results Seventy-five cases underwent the procedure successfully. The total procedure and fluoroscopic durations in group Ⅱ were significantly shorter than in group Ⅰ ［(150±23) min and (18±17) min versus (170±34) min and (25±16) min, P=0.03 and 0.04, respectively］. There was no significant difference in the fluoroscopic and procedure durations for geometry creation between group Ⅰ and group Ⅱ ［(8±4) min and (16±11) min versus (5±4) min and (14±8) min, respectively］. The fluoroscopic durations for CPVA were (15±5) min in group Ⅰ versus (10±6) min in group Ⅱ (P=0.05), and the CPVA procedural durations were significantly shorter in group Ⅱ than in group Ⅰ ［(18±11) min versus (25±10) min, P=0.04］. AF was terminated by radio frequency delivery in 14 cases (35%) in group Ⅰ versus 5 cases (14%) in group Ⅱ (P=0.035). After CPVA complete PV isolation was attained in 26 cases (65%) in group Ⅰ versus 11 cases (31%) in group Ⅱ (P=0.004). During a mean follow-up of 7 months, 32 (80%) cases in group Ⅰ and 24 (69%) cases in group Ⅱ were arrhythmia-free (P=0.06). One case developed pericardium effusion and another one case was found to have intestinal artery thrombosis in group Ⅱ. One case had moderate hemothorax in group Ⅰ. All the complications were cured by proper treatment. No PV stenosis was observed. Conclusions The CPVA procedure for atrial fibrillation is effective and safe. Although there is difference between the CARTO and the Ensite/NavX system, the CPVA procedure guided by either of them yields similar clinical results.     

RNA干扰血管紧张素Ⅱ1a型受体对肾血管性高血压大鼠血压及心肌肥厚的影响

目的用RNA干扰技术下调血管紧张素Ⅱ1a型受体(AT1a)表达,观察其对肾血管性高血压及其心肌肥厚重构的影响。方法构建两肾一夹(two-kidney,one-clip:2K1C)高血压大鼠模型,用携带U6启动子和AT1a特异短发夹RNA(shRNA)编码序列的质粒pAT1a-shRNA1,pAT1a-shRNA2单次尾静脉注射给药,以含非特异性shRNA编码序列的无关质粒pGenesil-Con(pCon)、选择性AT1受体拮抗剂缬沙坦每日灌胃给药干预3周,无干预为对照,检测尾动脉压变化和颈动脉压水平、左心室重量与体重之比(LV/BW),并用Western-blot分析组织AT1受体表达情况。结果尾动脉压(与干预前比较):Blank组及pCon组继续升高25mmHg左右,pAT1a-shRNA1、pAT1a-shRNA2组下降15~16mmHg,缬沙坦组下降约30mmHg;颈动脉压和左室/体重之比:pAT1a-shRNA1(194mmHg±5mmHg;2·27±0·37)、pAT1a-shRNA2(200mmHg±5mmHg;2·31±0·26)、缬沙坦组(164mmHg±5mmHg;2·26±0·39)显著低于对照组(234mmHg±10mmHg;3·24±0·38)及pCon组(232mmHg±7mmHg;2·94±0·06);与对照组相比,pAT1a-shRNA1、pAT1a-shRNA2组左心室(分别下降53·3%和47·8%)和主动脉(分别下降58·7%和49·3%)组织内AT1受体表达显著减少。结论RNA干扰AT1a受体有效地抑制了肾血管性高血压进展及其心肌肥厚重构。RNA干扰技术可能成为高血压病基因治疗的一种新策略。     

肺动脉高压对同种原位心脏移植患者移植后早期血流动力学的影响

目的分析研究心脏移植患者术前不同程度的肺动脉高压对患者移植后早期血流动力学指标、超声心功能检查、围术期并发症和死亡率的影响。方法回顾总结2004年6月至2006年12月,阜外心血管病医院连续做的67例同种原位心脏移植手术患者。根据术前肺血管阻力将患者分为3组：Ⅰ组无肺动脉高压、肺血管阻力等于或低于2．5Wood单位15例;Ⅱ组轻到中度肺动脉高压、肺血管阻力大于2．5Wood小于5．0Wood单位42例;Ⅲ组严重的肺动脉高压、肺血管阻力等于或大于5．0Wood单位10例。连续监测并记录麻醉前、术后即刻、12、24及48h的CVP、MPAP、CO、Sv02、PAWP等指标;停体外循环后、术后第1、3、7d、1个月、3个月经超声测定左室舒张末径（LVEDD）、左室射血分数（EF）及二、三尖瓣的返流情况等;术后详细记录各种并发症、治疗情况及术后30d的死亡率。结果本研究患者均完成心脏移植手术,3组患者无手术死亡（术后30d内）。Ⅲ组患者的术前EF值与Ⅰ组比较,P〈0．05;3组患者的体外循环阻断时间、供体心脏热缺血、冷缺血时间无明显差别;Ⅲ组患者的体外循环时间明显长于Ⅰ组、Ⅱ组P〈0．05,术后带管时间Ⅲ组与Ⅰ组比较,P〈0．05。3组间麻醉前MPAP、PVR,P〈0．05,Ⅲ组患者麻醉前CI明显低于Ⅰ组、PCWP明显高于Ⅰ组P〈0．05;Ⅲ组术后各时间点MPAP、PVR明显低于麻醉前、特别是术后48h,P〈0．05,但仍表现为肺动脉压升高。术后并发急性肾功能衰竭3例（Ⅱ组1例、Ⅲ组2例）、急性右心衰竭6例（Ⅰ组1例、Ⅱ组2例、Ⅲ组3例）。超声检查除Ⅲ组2例患者术后早期显示三尖瓣中量返流外,未发现明显的心脏扩大、收缩功能降低等异常情况。结论术前严重肺动脉高压患者心脏移植后早期肺动脉压力明显降低,但术后易发生急性右心衰竭等并发症,经积极的强心、利尿等治疗措施恢复良好。供体心脏的保护、围术期特别是术中及术后早期右心功能的维护、抗感染及排异反应的监测等是保证手术成功的关键。     

bFGF 对实验性近视眼动脉血液动力学的影响

目的:研究bFGF 对兔眼睑缝合法诱导的FDM 眼动脉血液动力学的影响,从而探讨bFGF 在近视眼 的发病机制中的作用。方法:单纯眼睑缝合法建立近视动物模型。取14 日龄幼兔45 只,分A、B、C 三组,每组 15 只。A 组:单纯缝合眼睑;B 组:缝合眼睑+结膜下注射bFGF+PBS;C 组:缝合眼睑+结膜下注射PBS. 均以右眼 为实验眼,左眼为对照眼。第60d,分别测量双眼屈光状态、眼周长度、眼动脉阻力及眼动脉收缩期和舒张期血 流流速。结果:A、C 两组眼睑缝合60d 后,与对侧眼相比诱导出相对近视,眼轴相对延长;而B 组屈光度和眼轴 长度双眼间差异无显著性。各组两眼间的眼动脉阻力及血流流速差异有显著性(P<0. 05);就实验眼而言A、C 两组间比较差异无显著性(P>0. 05),而B 组与A、C 两组间差异有极显著性(P<0. 01)。结论:眼睑缝合可引起 幼兔明显的轴性近视,伴随轴性近视出现眼动脉阻力增加、眼动脉血流流速减慢现象,而bFGF 可有效减低眼动 脉阻力、增加眼动脉血流流速。     

人VEGF_(165)和bFGF基因联合治疗大鼠急性心肌梗死

目的观察直接心肌内注射人血管内皮细胞生长因子(VEGF165)和碱性成纤维细胞生长因子(bFGF)基因对大鼠急性心肌梗死模型血管及梗死面积的治疗效果,评估比较联合应用2种基因与单纯应用一种基因的疗效。方法建立大鼠急性心肌梗死模型,将生理盐水(对照组)、空载体(A组)、VEGF165(B组)、bFGF(C组)、VEGF165和bFGF混合质粒(D组)分3点注射于梗死交界处心肌内,4周后取材做常规HE染色和Masson染色,分别测量各组微血管数量和梗死面积;用免疫组织化学染色鉴定VEGF、bFGF的表达。结果B组、C组和D组心肌毛细血管总数明显大于对照组和A组(P<0.01),D组毛细血管总数大于B组和C组(P<0.01)。D组和C组的梗死面积百分比小于其他3组(P<0.01),D组和C组之间差异无统计学意义(P>0.05)。VEGF和bFGF免疫组化染色显示有相应蛋白表达。结论联合应用VEGF和bFGF基因治疗急性心肌梗死,具有明显促进血管生成、缩小梗死面积的作用。