6-苄氨基嘌呤对大鼠小肠缺血再灌注损伤的影响

摘要

To explore the protective effects of 6-benzylaminopurine (6-BA) on ischemia/reperfusion (I/R) injury of small intestine of rats,eighty male SD rats were selected and randomly divided into four groups named control group,I/R model group,low and high dose 6-BA groups,respectively.Rats in low and high dose 6-BA groups were treated with 10,20 mg/kg 6-BA by gavage once daily for 3 weeks,and rats in control group and I/R model group were treated with the same volume physiologic saline.Superior mesenteric artery of rats in control group was not blocked after exposed,while it was blocked in I/R model group and low and high dose 6-BA groups for 30 min,and then the blood vessel was reperfused for 60 min.Then the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px),and MDA content in jejunum tissue of rats were measured.Cell DNA damage was observed by single cell gel electrophoresis method,and the expression of cysteinyl aspartate specific proteinase 3 (Caspase-3) was determined by immunity histochemistry method.The results showed as follows: compared with I/R model group,the supplementation of 10 and 20 mg/kg 6-BA significantly increased the activities of T-SOD and GSH-Px (P<0.05),and significantly decreased MDA content (P<0.05);broom shaped tails were less,and DNA content of tails and percentage of broom shaped tails were significantly decreased (P<0.05);Caspase-3 positively expressed cell count was significantly decreased (P<0.05).These results reveal that 6-BA has protective effects against injury of I/R in small intestine,and the effect of 20 mg/kg 6-BA is better.%本试验旨在研究6-苄氨基嘌呤(6-BA)对大鼠小肠缺血再灌注(I/R)损伤的保护作用.选取80只雄性SD大鼠,随机分为4组,即对照组、I/R模型组和低、高剂量6-BA组.低、高剂量6-BA组于术前3周分别连续灌胃10、20 mg/kg的6-BA,对照组和I/R模型组灌胃同体积的生理盐水,每天1次.对照组在暴露肠系膜上动脉后不做阻断;I/R模型组和低、高剂量6-BA组阻断肠系膜血管30 min后再灌注60 min.随后取大鼠空肠组织分别进行总超氧化物歧化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量检测;采用单细胞凝胶电泳法检测细胞DNA损伤程度,采用免疫组化法检测半胱氨酸天冬氨酸特异性蛋白酶3(Caspase-3)表达情况.结果显示,与I/R模型组相比,补充10、20 mg/kg的6-BA后,T-SOD、GSH-Px活性显著升高(P<0.05),MDA含量显著降低(P<0.05);小肠细胞DNA的拖尾现象好转,尾部DNA含量和拖尾率都显著低于I/R模型组(P<0.05);Caspase-3阳性表达细胞数量显著减少(P<0.05).由此可见,10、20 mg/kg的6-BA能有效防护I/R对小肠的损伤,且20 mg/kg的6-BA作用效果尤为明显.