中文摘要：

目的通过膜性肾病经典的动物模型被动Heymann肾炎（PHN），探讨足细胞自噬在膜性肾病病变过程中的作用，以及自噬激活可能的细胞内机制。方法SPF级健康雄性SD大鼠按随机数字表法分为5组即对照组、PHN2d组、PHN4d组、PHN7d组、PHN21d组，建立大鼠PHN模型。采用透射电镜观察足细胞形态和自噬泡，Weibel-Gomez点计数法计数单个肾小球足细胞数量，免疫组织化学染色检测肾小球内膜攻击复合物C5b-9的沉积与半胱氨酸天冬氨酸蛋白酶（caspase）-3的表达，原位缺口末端标记（TUNEL）法检测肾小球内细胞凋亡，Western印迹法检测肾小球自噬相关蛋白微管相关蛋白1轻链3（microtubule．associatedprotein1lightchain3，LC3）、葡萄糖调节蛋白（GRP）78、磷酸化蛋白激酶R样内质网激酶（phosphorylatedproteinkinaseR-likeERkinase，P．PERK）、磷酸化C．Jun氨基末端激酶（phosphorylatede．iunaminoterminalkinase，P-JNK）、活化转录因子6q（activatingtranscriptionfactor6a，ATF6ct）的表达。结果（1）造模后第4天起即可在肾小球内观察到C5b．9沿基底膜呈线状沉积。同时，透射电镜下可见上皮下少许颗粒状电子致密物沉积及足突融合，病变随时间呈加重趋势，至第21天可见典型膜性肾病改变。此外，尿蛋白定量结果显示，造模第3天起尿蛋白量即有明显升高，至第21天时可高达（50．6±6．0）mg／24h。（2）造模后第21天单位肾小球足细胞绝对数目较对照组显著下降（P〈0．05）。（3）caspase-3表达和TUNEL染色结果一致显示，造模后第21天肾小球内可检出凋亡的足细胞。（4）透射电镜和自噬标志LC3Ⅱ的检测结果均显示，造模后第7天和第21天足细胞的自噬水平均显著升高，但第21天LC3Ⅱ的表达较第7天有所回落。（5）造模后第2天即可检出GRP78高表达，至第7天时显著升高，而病变后期（第21天）又有所回落；同时，?

英文摘要：

Objective To investigate the role of autophagy in podocyte damage, and the intracellular mechanism of autophagy activation through passive Heymann nephritis （PHN） animal model. Methods Male Sprague-Dawley rats （n=40） were studied on day 0, 2, 4, 7, and 21 after induction of PHN by injection of anti-FxlA. Podocyte morphology and autophagosomes were observed by transmission electron microscopy. Podocyte numerical density was estimated by Weibel- Gomezmethod. Cell apoptosis was detected by TUNEL assay and caspase-3 immunohistochemical staining. Expressions of autophagy markers and endoplasmic reticulum stress （ERS）- associated proteins were analyzed by Western blotting. Results （1） In PHN rats, immunohistochemical staining showed that C5b-9 deposited along glomerular basement membrane on day 4 to day 21. Small subepithelial electron -dense deposits and a part of foot process fusion were detected in the glomerulus of PHN rats on day 4 by transmission electron microscope, and podocyte damage was aggravated on day 21. Furthermore, compared with control, the urinary protein levels of PHN rats began to increase on day 3, and reached the top on day 21 [（50.6±6.0） mg/24 hi. （2） The number of podocytes significantly decreased in PHN rats compared with control group on day 21（P 〈 0.05）. （3） In PHN rats, apoptotic podocytes were found by caspase- 3 immunohistochemical staining and TUNEL assay on day 21. （4） The expression of autophagy marker LC3 lI was markedly increased on day 7 and 21, but down- regulated on day 21 compared with day 7. Moreover, accumulated autophagosomes in podocytes were detected on day 7 and 21 by transmission electron microscope. （5） The level of GRP78 was significantly increased on day 2 and 7 but reduced to baseline on day 21. At the same time, the downstream pathways （ATF6α, p-PERK and p-JNK） of unfolded protein response were also up-regulated in the early process of PHN and down-regulated later. Conclusions Autophagy is an important way to protect agai