目的 将胚胎后肾间充质细胞移植到大鼠右肾包膜下，探讨移植细胞对宿主急性肾小管坏死（ATN）的保护作用。 方法 体质量相近的SD大鼠按随机数字表法分为正常对照（n＝24）、ATN（n＝35）、ATN加假手术（n＝37）、ATN加培养基（n＝36）、ATN加细胞移植（n＝29）共5组。首剂庆大霉素注射后第5、8、11、14天每组分别取6只大鼠处死，留取血和肾组织标本。4,6-联脒-2-苯基吲哚（DAPI）示踪法观察移植细胞的分布。全自动生化分析仪检测Scr和尿NAG酶水平。HE染色法进行肾组织病理评分。免疫组化染色检测肾皮质Ki-67和Bcl-2阳性表达细胞，分别计算增殖指数和Bcl-2蛋白的相对表达量。TUNEL法检测肾皮质细胞的凋亡指数。 结果 胚胎后肾间充质细胞被扩增，波形蛋白染色阳性，角蛋白染色阴性，符合未分化的间充质细胞的特点。与ATN组、ATN加假手术、ATN加培养基组大鼠比较，ATN加细胞移植组大鼠Scr和尿NAG酶较低[第14天 Scr：(101.38±20.46) μmol/L比(248.78±23.15)、(252.98±33.52)、(229.08±18.18) μmol/L；NAG酶：(14.83±7.74) U/L比（33.33±14.88）、（29.62±10.54）、（30.22±10.94）U/L，均 P < 0.05]；右肾皮质病理积分降低（P < 0.05）；肾小管上皮细胞增殖增加（P < 0.05），凋亡减少（P < 0.05）；Bcl-2蛋白表达水平上调（P < 0.05）。 结论 肾包膜下移植胚胎后肾间充质细胞能够修复损伤的肾脏，改善肾功能。

Objective To evaluate the nephroprotective effects of transplanting metanephric mesenchymal cells (MMCs) into the renal subcaspsule of rats with acute tubular necrosis (ATN) induced by gentamicin. Methods MMCs were expanded in culture and immunocytochemistry was used to characterize the cells. After gentamicin-induced ATN, fluorescence-labeled cells were transplanted and traced in kidney tissues by fluorescence microscopy. Serum creatinine(Scr) and N-acetyl-b-D-glucosaminidase(NAG) were tested. Kidney pathology was studied by hematoxylin-eosin staining. Apoptosis was examined by the TUNEL assay.Ki-67 and Bcl-2 expression was examined by immunohistochemistry. Results MMCs were expanded in culture and the phenotype of the cells was vimentin-positive and keratin-negative. Compared with other ATN groups, in the MMCs-treated group, Scr and NAG clearly decreased[14 d Scr: (101.38±20.46) μmol/L vs (248.78±23.15), (252.98±33.52), (229.08±18.18) μmol/L；NAG: (14.83±7.74) U/L vs(33.33±14.88), (29.62±10.54), (30.22±10.94) U/L, P<0.05, respectively]; the histopathologic lesion scores were lower(P<0.05); the Ki-67 antibody and apoptosis of renal tubular epithelial cells were improved or reduced respectively; the expression of Bcl-2 protein was up-regulated(P<0.05). Conclusion The subcapsular transplantation of MMCs can ameliorate renal function and repair kidney injury.