Sun Hui-Ming, Shi Yi, Song Yong, Lin Xin-Qing, Shen Xiao-Kun, Hong Ling-Zhi
Department of Respiratory Diseases, Clinical School of Nanjing University, Nanjing General Hospital of Nanjing Military Command, Nanjing 210002, China.
Zhonghua Yi Xue Za Zhi. 2009 Oct 20;89(38):2722-5.
To investigate the effects of heparin upon inflammatory reaction and associated mechanism of endotoxin-induced acute lung injury (ALI) in rat.
Thirty-six male Sprague-Dawley rats were randomly divided into three equal groups namely: ALI group, heparin treatment group and normal control group. The ALI rats were induced by injecting endotoxin intravenously and sacrificed at 4 h after model establishment. The lung histology was scored by a modification of Smith technique. The albumin permeability of pulmonary microvascular (P(alb)) was measured by single nuclide tracer technique. Tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and von Willebrand factor (vWF) levels of serum were determined using commercial enzyme-linked immunosorbent assay kits. The expressions of lung tissue extacellular signal-regulated kinases (ERK)-1/2, P38 mitogen-activated protein kinase (MAPK) and c-jun N-terminal kinases (JNK) were determined by Western blotting.
The Smith lung injury score in heparin treatment group and ALI group were (5.00 +/- 1.26) and (8.00 +/- 1.09) respectively. The values were significantly higher than that of normal control group (0.67 +/- 0.52, both P < 0.01). However, the Smith lung injury score in heparin treatment group was significantly lower than that of ALI group (P < 0.01). The P(alb), TNF-alpha, IL-6 and vWF of heparin treatment group were (0.28 +/- 0.04), (1.92 +/- 0.35) microg/L, (1.22 +/- 0.13) ng/ml and (24.9 +/- 4.0) U/L respectively. The values were significantly higher than those of normal control group [0.20 +/- 0.02, (0.51 +/- 0.09) microg/L, (0.23 +/- 0.05) ng/ml and (14.0 +/- 3.0) U/L respectively, all P < 0.01] but significantly lower than those of ALI group [(0.38 +/- 0.04), (2.77 +/- 0.37) microg/L, (1.62 +/- 0.13) ng/ml and (31.8 +/- 7.5) U/L respectively, all P < 0.01]. The lung tissue levels of phospho-ERK1/2 and phospho-P38 MAPK expressions of heparin treatment group were markedly higher than those of normal control group, whereas markedly lower than those of ALI group. There was no marked difference of phospho-JNK expression in all three groups.
Heparin markedly inhibits the expressions of phospho-ERK1/2 and phospho-P38 MAPK, down-regulates the inflammatory reaction, attenuates the endothelial permeability of pulmonary vasculature and significantly improves endotoxin-induced lung injury in rats.
探讨肝素对内毒素诱导的大鼠急性肺损伤（ALI）炎症反应的影响及其相关机制。
将36只雄性Sprague-Dawley大鼠随机分为三组，每组12只，即ALI组、肝素治疗组和正常对照组。通过静脉注射内毒素诱导ALI大鼠模型，造模后4小时处死大鼠。采用改良的Smith技术对肺组织学进行评分。采用单标记核素示踪技术测定肺微血管白蛋白通透性（P(alb)）。使用商用酶联免疫吸附测定试剂盒测定血清肿瘤坏死因子α（TNF-α）、白细胞介素6（IL-6）和血管性血友病因子（vWF）水平。采用蛋白质印迹法测定肺组织细胞外信号调节激酶（ERK）-1/2、P38丝裂原活化蛋白激酶（MAPK）和c-jun氨基末端激酶（JNK）的表达。
肝素治疗组和ALI组的Smith肺损伤评分分别为（5.00±1.26）和（8.00±1.09）。两组评分均显著高于正常对照组（0.67±0.52，P均<0.01）。然而，肝素治疗组的Smith肺损伤评分显著低于ALI组（P<0.01）。肝素治疗组的P(alb)、TNF-α、IL-6和vWF分别为（0.28±0.04）、（1.92±0.35）μg/L、（1.22±0.13）ng/ml和（24.9±4.0）U/L。这些值均显著高于正常对照组[分别为0.20±0.02、（0.51±0.09）μg/L、（0.23±0.05）ng/ml和（14.0±3.0）U/L，P均<0.01]，但显著低于ALI组[分别为（0.38±0.04）、（2.77±0.37）μg/L、（1.62±0.13）ng/ml和（31.8±7.5）U/L，P均<0.01]。肝素治疗组肺组织磷酸化ERK1/2和磷酸化P38 MAPK的表达水平明显高于正常对照组，而明显低于ALI组。三组磷酸化JNK表达水平无明显差异。
肝素显著抑制磷酸化ERK1/2和磷酸化P38 MAPK的表达，下调炎症反应，减轻肺血管内皮通透性，显著改善内毒素诱导的大鼠肺损伤。
