CAJ | 학술논문

目的观察低蛋白配伍α酮酸饮食对肾大部切除大鼠残肾组织硬化和肾素血管紧张素系统(RAS)的影响.方法 30只雄性SD大鼠建立肾大部切除的肾衰竭模型,1周后根据不同喂养分组如下:正常蛋白组(NPD组)予18%酪蛋白,低蛋白组(LPD组)予6%酪蛋白,低蛋白+α酮酸组(LK组)予5%酪蛋白+1%α酮酸,每组10只大鼠.另取10只雄性SD大鼠行假手术后予正常蛋白(18%酪蛋白)饲料作对照.12周后麻醉处死大鼠,常规检测生化指标和24 h尿蛋白定量.糖原染色法观察残肾组织的病理改变.免疫组化和Western印迹法检测残肾组织中转化生长因子(TGF-β1)、肾素(renin)和血管紧张素Ⅱ的1型受体(AT1R)的蛋白表达.实时PCR法检测renin和AT1R的基因表达.放免法和酶联免疫吸附法(ELISA)分别测定皮质匀浆和血浆中血管紧张素II(Ang II)的含量.结果术后12周大鼠的体质量,血清总蛋白和白蛋白水平在各组间的差异无统计学意义(均P>0.05).肾衰竭模型大鼠的血肌酐和尿蛋白水平均较对照组显著升高(均P<0.05),但3组间血肌酐水平的差异均无统计学意义(均P>0.05),而LK组的尿蛋白水平较NPD组和LPD组显著降低(均P<0.05).肾衰竭模型大鼠的肾小球硬化评分、ECM/肾小球面积之比和TGF-β1表达均显著高于对照组,而LK组和LPD组均显著低于NPD组(均P<0.05).肾皮质肾素、Ang II和AT1R的表达在LK组中均较NPD组显著降低(均P<0.05).结论在肾大部切除肾衰竭大鼠中,低蛋白配伍α酮酸饮食能在保证营养状态稳定的情况下减轻残肾组织的硬化,减少尿蛋白量,此肾脏保护作用可能与减轻肾脏局部RAS的活性有关.
목적 관찰저단백배오α동산음식대신대부절제대서잔신조직경화화신소혈관긴장소계통(RAS)적영향.방법 30지웅성SD대서건립신대부절제적신쇠갈모형,1주후근거불동위양분조여하:정상단백조(NPD조)여18%락단백,저단백조(LPD조)여6%락단백,저단백+α동산조(LK조)여5%락단백+1%α동산,매조10지대서.령취10지웅성SD대서행가수술후여정상단백(18%락단백)사료작대조.12주후마취처사대서,상규검측생화지표화24 h뇨단백정량.당원염색법관찰잔신조직적병리개변.면역조화화Western인적법검측잔신조직중전화생장인자(TGF-β1)、신소(renin)화혈관긴장소Ⅱ적1형수체(AT1R)적단백표체.실시PCR법검측renin화AT1R적기인표체.방면법화매련면역흡부법(ELISA)분별측정피질균장화혈장중혈관긴장소II(Ang II)적함량.결과 술후12주대서적체질량,혈청총단백화백단백수평재각조간적차이무통계학의의(균P>0.05).신쇠갈모형대서적혈기항화뇨단백수평균교대조조현저승고(균P<0.05),단3조간혈기항수평적차이균무통계학의의(균P>0.05),이LK조적뇨단백수평교NPD조화LPD조현저강저(균P<0.05).신쇠갈모형대서적신소구경화평분、ECM/신소구면적지비화TGF-β1표체균현저고우대조조,이LK조화LPD조균현저저우NPD조(균P<0.05).신피질신소、Ang II화AT1R적표체재LK조중균교NPD조현저강저(균P<0.05).결론 재신대부절제신쇠갈대서중,저단백배오α동산음식능재보증영양상태은정적정황하감경잔신조직적경화,감소뇨단백량,차신장보호작용가능여감경신장국부RAS적활성유관.
Objective To observe the influence of low protein diet with α-keto acid on kidney sclerosis and renin-angiotensin system in renal ablation rats. Methods Chronic renal failure rat model was established by renal ablation in 30 male SD rats,then the animals were randomly assigned to the following diet groups:normal protein group (NPD:18%casein protein),low protein group (LPD:6%casein protein) and supplemented low protein group (LK:5%casein protein+1%α-keto acids).Ten male SD sham-operated rats received 18%casein protein as control.All the rats were killed at the end of the 12th week.Pathologic changes were assessed by PAS staining.Ang II in homogenate and plasma were measured by radioimmunoassay and ELISA respectively.Immunohistochemistry and Western blotting were used to detect the protein expression of TGF-β1,renin and AT1R.Real-time PCR was used to detect the gene expression of renin and ATla,the main subtype of AT1 receptor. Results Body weight,total protein and serum albumin had not significant difference among the four groups(all P>0.05).Serum creatinine and proteinuria of nephrectomized rats were significantly higher compared to the control group (all P<0.05).Proteinuria of the LK group was lower than that of NPD and LPD groups (all P<0.05).Pathological results indicated fibrosis indices were significantly improved after LPD and LK intervention.Expressions of renin,Ang II and AT1R in LK group were significantly lower than those in NPD group (all P<0.05). Conclusions Low protein diet with α-keto acids supplement therapy exhibits renal protective effects of reducing urine protein excretion and improving renal fibrosis,which might be related to the attenuation of local renin-angiotensin system in activity nephrectomized rats.