烫伤延迟复苏后细胞凋亡对肠粘膜通透性的影响

Influence of enterocyte apoptosis on intestinal permeability after delayed resuscitation in scalded rats

目的 :探讨烫伤延迟复苏后肠粘膜细胞凋亡对其通透性的影响。方法 :150只Wistar大鼠分为立即复苏 (ER)、延迟复苏(DR) ,N -乙酰半胱氨酸 (NAC)和别嘌呤醇 (Allo)治疗组及正常对照。采用DNA片段百分率 (ap % )、电泳、TUNEL法观察回肠粘膜凋亡情况 ;并测定门静脉D -乳酸、内毒素以观察肠粘膜通透性改变。结果 :伤后DR组ap %均显著高于ER组。NAC组ap %显著低于DR组。电泳、TUNEL法均观察到肠粘膜凋亡发生 ;ap %与D -乳酸、内毒素变化呈显著正相关。结论 :烫伤延迟复苏后肠粘膜发生病理性凋亡 ,与其通透性变化密切相关 ;NAC可显著减轻延迟复苏所致肠粘膜细胞凋亡。

Objective: To discuss the influence of e nterocyte apoptosis on the permeability of intestinal mucosa after scald with delayed resuscitation. Methods: 140 Wistar rat s were divided into early resuscitation (ER), delayed resuscitation (DR), N-acetylcysteine (NAC) and allopurinol (Allo) treatment groups. 10 sham rats ser ved as control. Animals were subjected to 30% TBSA full-thickness scald. Apoptosis was identified by DNA fragmentation (ap %), DNA electrophoresis and TUNEL method. The permeability of intestinal mucosa were evaluated by levels of D-lactic acid and endotoxin in portal vein postburn. Results: The ap% in DR group was higher than that in ER group postb urn . The ap% in NAC group was lower than that in DR group. Typical DNA ladder and positive apoptotic cells were discerned by DNA electropho resis and TUNEL in DR group. A significant positive relationship existed between the ap% and the change of D-lactic acid an d endotoxin. Conclusion: Pathological apoptosis occurred in intestinal mucosa after scald and delayed resuscitation, r esulting in an increased intestinal permeability. NAC could block apoptosis of intestinal mucosa due to delayed resu scitation.