血红素氧合酶-1的诱导对肺缺血再灌注损伤的保护作用

目的探讨血红素氧合酶-1的诱导对肺缺血再灌注损伤的保护作用。方法将40只健康Sprague-Dawley大鼠随机分为4组：假手术对照（sham）组、肺缺血再灌注（I／R）组（阻断左肺门30min再灌注2h）、氯化血红素（Hemin）组（给予血红素氧合酶-1的诱导剂）与锌原卟啉（ZnPP）组（给予血红素氧合酶-1的抑制剂）。检测各组肺组织超氧化物歧化酶（SOD）活性,血浆肿瘤坏死因子（TNF-α）含量,观察肺组织湿干重比（W／D）以及电镜下肺组织超微结构变化。结果Hemin组肺湿／干重比（5．92±0．66）低于I／R组（7．55±0．66）（P〈0．01）,SOD活性（9．2±0．5）高于I／R组（2．8±0．4）（P〈0．01）,TNF-α含量（60．37±8．25）低于I／R组（452．26±22．59）（P〈0．01）,电镜下肺组织超微结构损伤改变明显减轻;而给予ZnPP（ZnPP组）后使上述改变发生逆转。结论血红素氧合酶-1的诱导可有效保护肺缺血再灌注损伤。

Protective effects of the induction of heme oxygenase-1 on ischemia reperfusion lung injury: in vivo experiment with rats

OBJECTIVE: To investigate the protective effects of the induction of heme oxygenase-1 (HO-1) on ischemia/reperfusion lung injury. METHODS: Forty Sprague-Dawley rats were randomly divided into four equal groups: sham group, lung ischemia/reperfusion injury (I/R) group, undergoing ligaturing of the left lung hilum for 30 minutes followed by reperfusion for 120 minutes; hemin group, undergoing intraperitoneal injection of hemin, an inducer of HO-1, 48 hours before the ligation and reperfusion; zinc protoporphyrin (ZnPP) group, undergoing intravenous injection of ZnPP, an inhibitor of heme oxygenase, 15 min after the ischemia-reperfusion; and sham operation group, undergoing sham operation. Two hours after the I/R arterial blood samples were collected and then the left lungs of the rats were taken out. Plasma tumor necrosis factor-alpha (TNF-alpha) and lung superoxide diamutase (SOD) activity were examined. Lung wet-to-dry weight (W/D) ratio was measured. The ultrastructure of the pulmonary alveoli and its capillaries were studied by using transmissional electromicroscopy. RESULTS: The lung W/D ratio of the hemin group was 5.92 +/- 0.66, significantly lower than that of the I/R group (7.55 +/- 0.66, P < 0.01), and that of the ZnPP group (7.34 +/- 0.39, P < 0.01). The SOD activity of the hemin group was 6.5 +/- 0.6 U/mg protein, significantly higher than those of the I/R group and ZnPP group (2.8 +/- 0.4 U/mg protein and 3.0 +/- 0.4 U/mg protein respectively, both P < 0.01). The plasma TNF-alpha was 180.36 +/- 12.46, significantly lower than those of the I/R and ZnPP groups (452.26 +/- 22.59 and 438.59 +/- 30.26 respectively, both P < 0.01). Transmissional electromicroscopy showed that the microscopic structure of the sham group was normal and that the pathological changes of hemin group were milder then those of the T/R and ZnPP groups. CONCLUSION: The induction of heme oxygenase-1 can protect effectively the lesion of lung pathology in ischemia reperfusion in vivo.