摘要
目的通过建立大鼠肾脏急性缺血/再灌注(I/R)及缺血预适应(I/P+I/R)模型,初步研究不同的缺血方式后肾脏核因子-κB(NF-κB)活性及二聚体亚单位的构成,探讨其减轻肾脏肾小管细胞凋亡的机制。方法 30只雄性SD大鼠摘除右肾、分离出左肾动脉后随机均分为3组(n=10):A组为假手术组(Sham组),只分离左肾动脉,暴露术野60 m in后直接缝合,24 h后取肾;B组为缺血/再灌注组(I/R组),持续夹闭左肾动脉45m in,恢复血供24 h后取肾;C组为缺血预适应+缺血/再灌注组(I/P+I/R组),左肾动脉夹闭2 m in,松开5 m in,重复3个循环,余同I/R组。分别用生化学方法检测血肌酐值的变化,组织病理学评价肾小管损伤程度评分,凝胶电泳迟滞分析检测肾组织NF-κB/DNA结合活性,超迟滞分析检测NF-κB亚单位的构成,Tunel法检测肾小管上皮细胞的凋亡。结果血清学检查及肾小管损伤评分提示,I/R组肾脏组织病理改变明显,损伤程度重,与Sham组比较,差异有统计学意义(P<0.05);与I/R组比较,I/P+I/R组损伤程度则明显减轻,差异有统计学意义(P<0.05)。凝胶电泳迟滞分析检测肾组织NF-κB/DNA结合活性I/P+I/R组明显高于Sham组,差异有统计学意义(P<0.05);超迟滞分析检测NF-κB亚单位含有p65、p50;差异有统计学意义(P<0.05)。结论肾脏缺血预适应可通过抑制NF-κB转录活性,减轻肾小管上皮细胞凋亡,从而发挥损伤保护效应。
Objective To investigate the effect of different modes of renal ischemia on the activity of NF-κB and the composition of dimeric subunit and to explore the causative mechanism underlying the attenuated apoptosis of renal tubular cells with the establishment of animal models of acute renal ischemic/reperfusion（I/R） and ischemic preconditioning（I/P＋I/R） in rats.Methods 30 male Sprague-Dawley rats were randomized into 3 groups（n=10 each） following right nephrectomy and isolation of the left renal artery.Group A served as the sham-operated control,only with isolation of the left renal artery and suture following exposure for 60 min.Group B（I/R group） rats were subjected to ischemia for 45 min by clamping of the left renal artery and subsequent resumed blood supply.Group C（I/P＋I/R） rats were pre-treated with 3 cycles of 2-minute ischemia and 5-minute reperfusion.All the rats were sacrificed at 24 h and nephrectomy was performed for analysis,including biochemical determination of the serum creatinine,histopathological evaluation of the renal tubules,electrophoretic mobility shift assay（EMSA） of renal NF-кB/DNA binding activity,super shift assay of the composition of NF-κB complexes in renal tissues and terminal deoxynucleotidyl transferase dUTP nick end labeling（TUNEL） assay of the apoptosis of renal tubular epithelial cells.Results Serological examinations and scores of renal tubular injury revealed evident histopatological changes and serious injury in renal tissues in group B.Compared with the sham group,the differences were statistically significant（P0.05）;Compared with group B,group C had markedly attenuated injury with significant statistical differences（P0.05）;EMSA results showed that the renal NF-кB/DNA binding activity was significantly higher in group C than in group A,with significant statistical differences（P0.05）;and super shift assay of the composition of NF-κB dimeric subunit confirmed the presence of p65 and p50 in group C,with significant statistical differences（P0.05）.Conclusion Renal ischemic preconditioning attenuates the apoptosis of renal tubular epithelial cells via the inhibition of the transcriptional activity of NF-кB,and thus has the protective effect on renal tissues.
出处
《徐州医学院学报》
CAS
2010年第7期421-425,共5页
Acta Academiae Medicinae Xuzhou
基金
国家自然科学基金(30670984)
