褪黑激素对心肌缺血再灌注损伤的保护作用

目的 :探讨褪黑激素增补于停搏液中对缺血再灌注离体鼠心的保护作用。方法 :将 2 4只Wistar大鼠随机分为褪黑激素组 ,对照组。离体鼠心在改良的Langendorff Neely灌注模型上 30min预灌注 ,12 0min停搏 ,30min再灌注。缺血前及再灌注期间测定血流动力学指标 ,心肌酶 (CPK ,LDH)、心肌超氧化物歧化酶(SOD)、过氧化脂质 (LPO)含量。电镜观察心肌超微结构。结果 :再灌注后 ,褪黑激素组心功能、心肌超微结构的改善明显优于对照组 ;CPK ,LDH ,LPO含量显著低于对照组 (P <0 .0 1) ;SOD含量显著高于对照组 (P <0 .0 1)。结论 :褪黑激素增补于停搏液中可显著减轻心肌缺血再灌注损伤 ,具有良好的心肌保护作用     

转化生长因子-β1对心脏移植排斥反应中心肌细胞凋亡的影响

目的:探讨转化生长因子-β1(TGF-β1)对心脏移植排斥反应中心肌细胞凋亡的影响。方法:采用大鼠颈部心脏移植模型,随机分为3组:对照组、移植组、TGF-β1组,分别于术后第1、3、5、7天各取4只移植心脏,原位末端标记(TUNEL)法染色检测心肌细胞凋亡,以心肌细胞凋亡阳性细胞数占总心肌细胞数的百分比作为心肌细胞凋亡指数(AI)。用免疫组化方法观察Bcl-2、Bax的表达情况。结果:移植组心肌细胞于术后第1天即出现凋亡,第3天明显增加,第7天达高峰。TGF-β1组各时间点心肌细胞AI明显小于对应的移植组(均P<0.01)。与移植组相比,TGF-β1组心肌细胞Bax表达明显降低(P<0.01)。结论:TGF-β1对心脏移植排斥反应中心肌细胞凋亡有显著抑制作用,可能与其下调Bax表达,提高Bcl-2/Bax比值有关。     

落新妇甙对小鼠心脏移植排斥反应的抑制作用

目的探讨落新妇甙对小鼠心脏移植排斥反应的抑制作用。方法采用小鼠颈部心脏移植模型。随机将心脏移植后的48只小鼠分为四组：A组心脏移植后每天用生理盐水1ml灌胃，B组心脏移植后每天用环孢素A5mg／kg灌胃，C组心脏移植后每天用落新妇甙1ml／kg灌胃，D组心脏移植后每天用环孢素A2．5mg／kg及落新妇甙1ml／kg灌胃。观察移植心脏的存活时间及心脏跳动情况。结果B组、C组及D组移植心脏存活时间均较A组显著延长（P＜0．01）；D组移植心脏存活时间最长，优于C组（P＜0．05）和B组（P＜0．01）。结论落新妇甙对心脏移植排斥反应有较强的抑制作用，并与环孢素A有协同作用。     

A new carotid artery transplantation model of rats

To establish a murine carotid artery transplantation model for the study of the chronic rejection, 80 rats were divided into two groups, an allotransplant （ACI-Lewis） group and an isotransplant （Lewis-Lewis） group （control group）. The donor carotid artery and the recipient carotid artery were anastomosed by using a polyethylene cuff （internal diameter： 0.7 mm, length： 3 mm）.The pathological changes of carotid artery transplant were observed 14, 28 and 56 days after the transplantation. The results showed that the model was successfully established in 95% of the animals. The chronic rejection-associated arteriosclerosis was induced 28 days after the transplantation. The new chronic rejection model of carotid artery by using cuff technique caused fewer traumas and was easy to make. The pathological changes of the transplant mimicked the chronic rejection-associated arteriosclerosis found in human transplant.     

The inhibitory effect of astilbin on the arteriosclerosis of murine thoracic aorta transplant

The inhibitory effect of astilbin on transplant arteriosclerosis in murine model of thoracic aorta transplantation was examined. Model of rat thoracic aorta transplantation was established. Ninety rats were divided into three groups. In isograft group, the thoracic aorta of Brown Norway （BN） rat was anastomosed with the abdominal aorta of another BN rat. In allograft group, the thoracic aorta of BN rat was anastomosed with the abdominal aorta of Lewis rat. In astilbin group, the rats receiving allo-transplantation were given astilbin 5 mg/kg per day for a time of 28 days. The donor thoracic aorta and the recipient abdominal aorta were anastomosed by means of a polyethylene can- nula （inner diameter： 1.5 mm, length： 3 mm length）. The grafts were histologically examined for structural changes. The areas of arterial lumen and endatrium were calculated. Our results showed that, in the allograft group, 28 days after allografting, conspicuous proliferation of smooth muscles and infiltration with a great number of inflammatory cells were found in the tunica intima and tunica media. Astilbin significantly inhibited the proliferation of smooth muscles and ameliorated the infiltration of inflammatory cells thereyby prevent against the development of transplant arteriosclerosis. It is concluded that asltilbin can effectively prevent the development of arteriosclerosis in allotransplant by inhibiting the proliferation of smooth muscles and inhibit the proliferation of smooth muscles in tunica of intima and media and reducing infiltration of the inflammatory cells.     

小鼠颈部异位心脏移植模型的改进

0 引言随着移植免疫研究对供、受体间种系纯化程度要求的日益提高,小鼠正成为器官移植的理想动物. 我们在成功建立大鼠腹部、颈部异位心脏移植模型的基础上,对已建立的小鼠颈部心脏移植模型加以改进[1,2].     

套管改良法建立大鼠颈部心脏移植模型

目的:采用套管改良技术建立大鼠颈部心脏移植模型和研究心脏移植再灌注损伤。方法:采用同系移植,供受体均为SD大鼠。用0.7mm内径聚乙烯管做内置管,将供心的无名动脉与受体右颈总动脉连接;用1.5mm内径聚乙烯管做内置管,将供心的肺动脉与受体右颈外静脉连接。结果:正式实验30次,手术成功率97%。手术时间和供心热缺血时间显著缩短,手术成功率明显提高。结论:套管改良法简单实用,无须血管吻合技术,为器官移植研究提供了更为方便、快捷的方法,值得推广。     

白细胞介素-15在心脏移植排斥反应中的表达及意义

目的 探讨白细胞介素-15（IL-15）在心脏移植排斥反应中的表达及其与排斥反应的关系。方法 采用小鼠颈部心脏移植模型，随机分为2组：同基因移植组，供、受体均为C57BL／6小鼠；异基因移植组，供、受体分别为BALB／C、C57BL／6小鼠。以pactin作内参照，分别于术后第1、3、5、7天取移植心脏，用逆转录-聚合酶链式反应（RT—PCR）法观察IL-15的表达情况。结果 随着术后天数的增加，异基因移植组IL-15表达逐渐升高，第5天达高峰（与同基因移植组相比，P〈0．01）。结论 IL-15的表达与心脏移植急性排斥反应的发生发展密切相关，可作为心脏移植急性排斥反应的监测指标，对急性排斥反应的早期诊断和移植物的预后估计具有重要的临床意义。     

大鼠腹部异位心脏移植术的改进

目的：改进大鼠腹部异位心脏移植术和研究心脏移植排斥反应。方法：将陈忠华术式加以改进，将血管吻合口改在肾静脉和腰静脉之间，结扎但不切断下腔静脉背支，肉眼下直接进行心脏移植血管吻合。结果：手术成功率90％（63／70），不需手术显微镜。结论：本术式操作简单实用，易于推广。