大鼠肝肾联合移植急性排斥反应中细胞凋亡的动态研究

REJECTION-ASSOCIATED APOPTOSIS OF SIMULTANEOUS LIVER-KIDNEY TRANSPLANTATION IN RATS

目的:研究肝肾联合移植术(SLKT)后排斥反应与细胞凋亡的关系并观察雷帕霉素(RAPA)对移植后排斥反应的抑制作用。方法:①建立动物模型:雄性SD大鼠50只,Wistar大鼠30只,随机、配对分为4组,每组10对,并施行SLKT。Ⅰ组为SD→SD为对照组;Ⅱ组进行Wistar→SDSLKT,术后不予免疫抑制治疗;Ⅲ组为Wistar→SDSLKT,术后即予以RAPA1 mg/kg·d-1灌胃;Ⅳ组为Wistar→SD SLKT,术后即予以RAPA 2mg/kg·d-1灌胃;②于1、3、5、7 d分别处死5只大鼠,获取移植肝、移植肾组织行病理学检查和细胞凋亡实验。结果:各组实验术后1、3 d均未发现排斥反应,Ⅱ组术后5、7d分别出现1度、2度排斥征象,Ⅲ组仅在7d出现早期排斥反应征象,Ⅳ组在术后一直未见排斥征象。肝细胞、肾小管上皮细胞凋亡数量在排斥反应前期和排斥反应时显著增加,不同强度的排斥反应,细胞凋亡数量差异有统计学意义(P<0.05)。结论:SLKT后急性排斥反应中出现较多的肝、肾小管上皮细胞凋亡,其始发时间早于排斥反应的组织学发现,凋亡数量与排斥反应强度呈正相关,可作为SLKT后急性排斥反应的另一种可信的标志物;RAPA对急性排斥反应有较强的抑制作用,其抑制能力与剂量呈正相关。

Objective:To investigate the relation after simultaneous liver-kidney transplantation(SLKT) and the effects of rapamycin on rejection.Methods:The liver and kidney of donor were ablated simultaneously,and then the model of SLKT was established.Pseuooperated SD(SD→SD)rats were used as control group by simultaneous liver-kidney reansplantation(groupⅠ).By using a model of liver-kidney allotransplanted rats(SD→Wistar),based on different treatment,the rats were divided into rejection group(group Ⅱ),rapamycin(1 mg/kg·d-1)-treated group(group Ⅲ),rapamycin(2 mg/kg·d-1)-treated group(group Ⅳ).Extract blood to examination serum ALT and Cr in all rats;Five rats were killed on the day 1,3,5 and 7 in each group postoperatively.The graft was harvested for the examination of pathology and assay of apoptosis.Results:The pathological evidences of rejection were not detected in all rats on days 1 and 3 after operation.There episodes of Ⅰ° and Ⅱ° rejection in group Ⅱ on days 5 and 7 after operation respectively.On day 7 after operation,the mild rejection occurred in the group Ⅲ and no rejected trail existed in the group Ⅳ.The quantity of apoptosis was increased in the early stage and episode of graft rejection.There was a significant difference in the quantity of apoptosis among different stages of rejection(P<0.01).Rapamycin did not cut down the course of rejection.Conclusion:A large number of apoptotic hepatocyte and tubular epithelial cells would apparent during the course of rejection.It could be another reliable indicator for pathologic findings of rejection and have positive correlation with progressive acute rejection.The immunoppression of rapamycin depends on the dose.