中图分类号R692.5
文献标识码A文章编号1000-1492(2000)02-0101-04
Establishment of model in chronic renal
insufficiency of rats
Xiong Zuying, Ding Changhai, Zhang Baike et al
(Dept of Nephrology, The 1st Affiliated Hospital of Anhui Medical University,Hefei230022)
AbstractObjectiveTo establish a special animal model of chronic renal inefficiency (CRI) in Wistar rats. MethodsAt 1 week after right kidney of rats was removed by operation, some rats were received adriamycin (Adr) twice (5 and 3 mg·kg-1, respectively) at 3 week intervals. All animals were divided into 4 groups: control, right kidney nephrectomy (RKX), Adr, and CRI. Urinary protein excretion (UPE) of 24 hours in all rats was observed at 2 to 12 weeks, and plasma biochemical parameters and histological examination were investigated at 3rd month. ResultsIn the third month after Adr administration, besides the typical nephrotic syndrome, the levels of blood urea nitrogen and plasma creatinine were increased more (P<0.01) in group CRIthan that in control. The level of osmolality was remarkably decreased. Histologically, mesangial cellularity slightly increased and extracellular matrix significantly expanded in the majority of glomeruli. Tubules showed apparently focal atrophy and many proteincasts were found in dilated tubules. Moderate fibrosis in interstitium was also observed. ConclusionRenal injury may be induced by RKX or Adr administration, and CRI is produced in combination with RKX and Adr administration in three months.
MeSHkidney failure, chronic; disease model, animal; rats
动物模型是研究慢性肾功能衰竭不可缺少的手段,寻找病变稳定、重复性好的慢性肾功能不全(chronic renal insufficiency, CRI)模型,对于探讨慢性肾脏疾病进行性发展的机制、发现能有效阻止其进展的药物,具有极为重要的意义〔1~5〕。阿霉素肾病(adriamycin-induced nephropathy, AIN)是较为常用的一种药物性肾病模型〔6〕,长时间(6~9月)的观察可模拟人类CRI。但研究时间较长也为实际应用带来了一定困难,为缩短观察时间,制备出稳定的CRI动物模型,本研究在AIN模型基础上,通过反复实验改进,制作成大鼠右肾摘除联合AIN肾硬化模型,即CRI动物模型,现报道如下。
1材料与方法
1.1实验动物Wistar大鼠,♀,3~4月龄,体重170~210 g,由安徽医科大学动物实验中心提供(皖医实动准01号)。自由饮水、进食。饲料成份如下:碳水化合物54.52%,蛋白质22.38%,脂肪4.50%,钙1.20%,磷0.75%,镁0.28%,复合维生素1.00%,微量元素1.00%,其它14.45%。饲养1周后使用。
1.2主要设备和试剂阿霉素(adrimycin,Adr)每支10 mg,日本明治制药株式会社产品,使用前用生理盐水稀释;普通大鼠饲养笼和代谢笼若干。
1.3模型制备方法用戊巴比妥钠(30 mg·kg-1)麻醉动物,常规消毒,腹部正中切口打开腹腔,找出右肾,分离出肾上腺。结扎肾蒂,取出右肾,向腹腔内加入青霉素钠10万U后关腹。模型组(CRI)为右肾切除后1周经尾静脉注射Adr 5 mg·kg-1,首次注射后3周再注射Adr 3 mg·kg-1。手术动物死亡率为20%。于首次注射Adr后3个月处死大鼠,检测相关指标。
1.4实验分组及步骤术后1周,将受试大鼠分为4组:即正常组;右肾摘除组(RKX);Adr注射组(Adr):单次静注Adr 5 mg·kg-1;CRI组:RKX后2次静注Adr。室温(<20℃)下留取2~12周时大鼠24 h尿液,测定尿蛋白。3个月时,取大鼠心脏血测血脂、血浆蛋白、尿素氮(BUN)和肌酐(Cr),并摘除肾脏进行病理学检查等。血浆生化指标由全自动生化分析仪完成。尿蛋白按考马斯亮蓝方法进行测定。尿渗透压(Osmolality)采用冰点法测定。
1.5肾组织病理学检查肾组织固定后,常规脱水、透明浸蜡、包埋,切片厚约2 μm,经HE、PAS、Masson和PASM染色后,由固定的病理检验人员进行病理学诊断,先将各组切片观察一遍,了解各组病变程度。每个动物肾小球损害程度按改良方法〔7〕进行评价。
1.6统计学方法所有实验结果采用±s表示,并采用单因素ANOVA方差分析,q检验比较组间差异。
2结果
2.1各组大鼠尿蛋白排泄量(UPE)变化趋势自首次注射Adr后2~12周各组大鼠的UPE变化趋势见图1。由图1可见,RKX组大鼠UPE无显著变化,仅12周时明显高于正常组,但仍大大低于其它两组;Adr组大鼠UPE持续增加,至第6周后稳定在每日400~500 mg;CRI组亦呈类似改变,但与Adr组相比差异无显著性,表明单侧肾切除后,在3个月的观察时间内并不明显增加Adr大鼠的UPE。
表13个月时慢性肾功能不全大鼠的血浆参数(±s,n=4)
组别 TP(g·L-1) ALB(g·L-1) CH(mmol·L-1) TG(mol·L-1) 正常组62.3±6.1
42.1±3.5
1.54±0.27
0.60±0.14 RKX组 63.1±5.7 44.7±4.0 1.68±0.23 0.62±0.11 Adr组 40.2±5.2** 23.6±1.7** 4.56±0.66** 1.81±0.32** CRI组 38.7±4.6** 20.9±1.4**# 5.48±0.63**# 1.92±0.28**
与正常组相比:**P<0.01 ;与Adr组相比:#P<0.05
表23个月时慢性肾功能不全大鼠的肾功能变化(±s, n=4)
组别 BUN(mmol·L-1) Cr(μmol·L-1) Ccr(ml·min-1.100 g-1) Osmolality(mOsmol·kg-1) 正常组8.48±2.17
48.55±9.13
0.52±0.08 1 683.5±276.3 RKX组 10.52±3.01 61.90±17.44 0.42±0.07* 1 433.1±232.7 Adr组 18.41±4.22** 110.35±27.58** 0.29±0.06* 827.2±161.5** CRI组 30.86±9.05**# 143.15±36.05**# 0.15±0.04**# 548.9±108.3**#
与正常组相比:*P<0.05, **P<0.01; 与Adr组相比:#P<0.05
图1慢性肾功能不全大鼠的尿蛋白排泄量变化
±s,n=4,与对照组相比:P<0.05,P<0.01
2.2血浆蛋白和血脂水平变化3个月时,Adr组和CRI组大鼠血浆总蛋白(TP)和白蛋白(ALB)水平明显降低,其中CRI组的降幅更为显著;两组大鼠的总胆固醇(CH)和甘油三酯(TG)则明显增加,且CRI组的
