犬小肠缺血再灌注后NO和SOD的改变及免疫细胞凋亡基因的表达

Changes of NO and SOD and expression of apoptotic gene of immunocytes in intestinal ischemia and reperfusion in dogs

目的 :研究小肠缺血再灌注后一氧化氮 (NO)和超氧化物岐化酶 (SOD)浓度的改变及Bax、c Fos和增殖性细胞核抗原 (PCNA)在小肠粘膜白细胞和淋巴细胞的表达 .方法 :阻断分布小范围细小小肠动脉 ,建立缺血再灌注模型 .分别于动脉阻断前、开放后 0 ,30及 6 0min从伴行静脉抽取血液标本 ,检测NO和SOD的浓度 .以免疫组织化学SP法研究Bax ,c Fos和PCNA在小肠粘膜固有层白细胞和淋巴细胞的表达 .结果 :与血管阻断前相比 ,NO和SOD浓度明显下降 .再灌注 0 ,30和 6 0min后NO的浓度分别是 (12 .1± 4 .6 ) ,(11.6± 4 .4 )和 (15 .5± 4 .8) ,SOD的浓度分别是 (75 .0±4 .5 ) ,(4 3.4± 11.4 ) ,(90 .3± 2 7.9)× 10 3 NU·L -1.再灌注0 ,30和 6 0min ,Bax阳性细胞率分别为 (5 4± 8) ,(80± 5 )和(70± 7) ,c Fos阳性细胞率分别为 (85± 3)、(92± 5 )和 (6 0±4 ) ,PCNA阳性细胞率分别为 (90± 5 ) ,(93± 4 )和 (5 7± 3) .结论 :小肠小范围缺血再灌注后NO和SOD浓度的下降提示氧自由基的增多 ,Bax ,c Fos和PCNA的表达改变可能在小肠粘膜固有层白细胞和淋巴细胞的免疫损伤。

AIM: To study the concentration changes of nitric oxide (NO) and superoxidedismutase (SOD), and the expression of Bax, c fos and proliferation cell nuclear antigen (PCNA) after ischemia and reperfusion of intestines in dogs. METHODS: The intestinal ischemia reperfusion model was established by clamping the intestinal arteries distributing in small area. Blood samples from accompanying intestinal veins were collected before clamping the artery and at 0, 30 and 60 min after reperfusion to examine the concentration of NO and SOD. The expression of Bax, c fos and PCNA of neutrophils and leukocytes in intestinal propria mucosae was detected by means of immunohistochemical method. RESULTS: The concentrations of NO and SOD decreased and the expression of Bax, c fos and PCNA increased in neutrophils and leukocytes of intestinal propria mucosae after reperfusion. At 0, 30 and 60 min after reperfusion, the concentration of NO was respectively (12.1 ±4.6), (11.6±4.4) and (15.5±4.8) μmol·L -1 , that of SOD was (75.0±4.5), (43.4±11.4) and (90.3±27.9)×10 3 NU·L -1 , the positive cell rate of Bax was (54± 8), (80±5) and (70±7), that of c fos was(85±3), (92±5) and (60±4), and that of PCNA was (90±5), (93±4) and (57±3). CONCLUSION: Decrease NO and SOD concentration after ischemia reperfusion in small area of intestines indicates the increase of oxygen radicals. The changes of related gene expression in neurtrphils and leakocytes of propria mucosae may play an important role in inflammatory injury, apoptosis and other pathological changes.