Zhang Cheng, Sheng Zhi-Yong, Hu Sen, Gao Jian-Chuan, Yu Sheng, Liu Yi
Department of Burns and Plastic Surgery, Lanzhou General Hospital, Gansu Province 730050, Lanzhou, PR China.
Burns. 2002 Dec;28(8):731-7. doi: 10.1016/s0305-4179(02)00210-3.
To study the influence of apoptosis of intestinal epithelial cells occurring as a result of reperfusion after burn shock on the intestinal barrier.
Fifty Wistar rats were subjected to a 30% TBSA full thickness burn, and normal saline (40 ml/kg) was given intraperitoneally immediately after the injury (group A). Ten rats served as a sham control group. The experimental group B consisted of 50 rats with identical injuries, but the normal saline was not given until 6h after the injury. Apoptosis of intestinal epithelial cells was verified by DNA fragmentation, DNA agarose gel electrophoresis, TUNEL and electron microscope (EM), and DNA fragmentation rate was expressed as ap%. The D-lactic acid in portal vein blood and intestinal diamine oxidase (DAO) were determined to evaluate the permeability and integrity of intestinal mucosal epithelium.
The ap% of intestinal epithelium group B was higher than in that of group A (P<0.05 or 0.01), and its amplitude peaked at 12h for both groups. Typical DNA ladder pattern was seen in electrophoresis in both groups. Apoptotic cells were discerned on the tips of the ileal villi at 3h postscald by TUNEL and EM in the group B, and they appeared earlier than in the group A. There was a significant positive correlation between the ap% and the level of D-lactic acid (group A: r=0.817, P<0.05; group B: r=0.727, P<0.05). On the other hand, a significant negative correlation was found between the ap% and the DAO values (group A: r=-0.937, P<0.01; group B: r=-0.836, P<0.05).
Apoptosis occurred in enterocytes after scald injury this pathological change might contribute to a breach of integrity of intestinal epithelium, leading to a compromise in its barrier function. Delayed fluid resuscitation might lead to an earlier and higher degree of apoptosis of the intestinal epithelial cells.
研究烧伤休克后再灌注所致肠上皮细胞凋亡对肠道屏障的影响。
50只Wistar大鼠行30%体表面积全层烧伤，伤后立即腹腔注射生理盐水（40 ml/kg）（A组）。10只大鼠作为假手术对照组。实验组B由50只伤情相同的大鼠组成，但伤后6小时才给予生理盐水。通过DNA片段化、DNA琼脂糖凝胶电泳、TUNEL和电子显微镜（EM）检测肠上皮细胞凋亡情况，DNA片段化率用ap%表示。检测门静脉血中D-乳酸和肠二胺氧化酶（DAO），以评估肠黏膜上皮的通透性和完整性。
B组肠上皮细胞的ap%高于A组（P<0.05或0.01），两组的ap%在12小时达到峰值。两组电泳均可见典型的DNA梯形条带。TUNEL和EM检测显示，B组伤后3小时在回肠绒毛顶端可见凋亡细胞，且出现时间早于A组。ap%与D-乳酸水平呈显著正相关（A组：r=0.817，P<0.05；B组：r=0.727，P<0.05）。另一方面，ap%与DAO值呈显著负相关（A组：r=-0.937，P<0.01；B组：r=-0.836，P<0.05）。
烫伤后肠上皮细胞发生凋亡，这种病理变化可能导致肠上皮完整性破坏，进而使其屏障功能受损。延迟液体复苏可能导致肠上皮细胞更早、更严重的凋亡。
