摘要
目的:观察烫伤延迟复苏后肠粘膜上皮细胞凋亡的发生规律及与氧自由基损伤的关系。方法:150只雄性Wistar大鼠随机分为A组(烫伤立即复苏组,n=60)、B组(烫伤延迟复苏组,n=50)、C组(N-乙酰半胱氨酸(NAC)治疗组,n=20)和D组(别嘌呤醇治疗组,n=20)。30%TBSA三度烫伤大鼠伤后6小时进行复苏;采用DNA断裂百分率(ap%)、琼脂糖凝胶电泳和DNA片段原位末端标记(TUNEL)法观察伤后肠粘膜上皮细胞凋亡发生规律;并测定了A组、B组伤后3、6、12、24、48小时和C组、D组伤后12、24小时肠粘膜丙二醛(MDA)、黄嘌呤氧化酶(XO)、总巯基(TSH)和非蛋白巯基(NPSH)的变化。结果:A组和B组伤后肠上皮均发生严重的细胞凋亡,高峰期在伤后12和24小时,但B组凋亡发生早且更严重;烫伤后肠粘膜MDA、XO均呈上升之势,而TSH和NPSH则呈逐渐下降之势。C组伤后肠粘膜ap%、MDA显著低于B组,而NPSH含量则显著高于B组。D组肠粘膜XO水平显著下降,但其ap%无显著变化。B组肠粘膜ap%与MDA和XO变化成显著正相关(P<0.05或0.01);而与NPSH的变化则成显著的负相关(P<0.05)。结论:延迟复苏可使烫伤后肠上皮细胞凋亡率显著上升;肠粘膜上皮细胞凋亡发生与其氧化应激关系密切;抗氧化剂NAC可有效降低肠上皮细胞凋亡,提供一定的保护作用。
To observe the apoptosis of enterocytes after scald with delayed resucitation in rats and the relationship with its oxygen free radical(OFR)injury. Methods: 150 male Wistar rats were divided randomly into four groups: group A, prompt resuscitation , n=60; group B, delayed resuscitation, n=50;group C, N-acetyl-cysteine(NAC) treatment,n=20;Group D, allopurinol treatment, n=20. Animals were subjected to 30% TBSA scald with delayed resuscitaton at 6 hours postscald. Apoptosis of enteroeytes was identified by DNA fragmenta-tion(ap%) detection , DNA agarose gel electrophoresis, TUNEL histochemistry method . The contents of malon-dialdehyde(MDA), total thiol(TSH), non-protein thiol(NPSH) and the activity of XO in intestinal mucosa were determined at different timepoint postburn in four groups. Results:The ap% of intestinal epithelial cells increased significantly in group A and B. The peaks were at 12h for group A and B. The ap% in group B was much earlier and higher than in group A from 3h to 48h postscald (P<0. 05～0. 01). This corresponded with the results ob-served by electrophoresis and TUNEL method . The levels of intestinal MDA and XO increased dramatically ,but the contents of intestinal TSH and NPSH decreased significantly postscald in group A and B. The levels of ap% and MDA in group C were much lower than in group B,but the NPSH was higher in group C. The activity of XO decreased significantly ,no significant change in ap% was observed in group D, compared with group B. There was a significant positive relationship between the enterocyte ap% and the content of MDA in group B, but for the change in NPSH, the relationship was negative(for MDA: r=-0. 937,P<0.01;for NPSH : r= -0.836P<0. 05). Conclusion:Significant apoptosis of enterocytes was induced by delayed resuscitation after scald in rats. A close relationship existed between apoptosis and the oxygen stress in intestinal mucosa. NAC can decrease the in-testinal apoptosis caused by OFR postburn.
出处
《感染．炎症．修复》
2000年第1期11-15,共5页
Infection Inflammation Repair
关键词
烧伤
细胞凋亡
小肠
氧自由基
大鼠
Burn Apoptosis Enterocyte Oxygen free radical Rat
