Zhou Junlin, Zhu Xiaoguang, Zhang Guisheng, Ling Tong
Department of Hand Surgery, Third Affiliated Hospital, Hebei Medical University, Shijiazhuang 050051, China.
Chin J Traumatol. 2002 Apr;5(2):86-91.
To determine the role of hemoglobin (HB) induced heme oxygenase-1 (HO-1) in injured lungs caused by limb ischemia-reperfusion (I/R) in rats.
A rat model of ischemia in the hind limbs was made by clamping the infrarenal aorta with a microvascular clip, and lung injury occurred after reperfusion. To induce the expression of HO-1 in the lungs, Hb was administrated intraperitoneally at 16 hours before reperfusion. Northern blotting and Western blotting were used to detect the expression of HO-1 in the lungs, and the carboxyhemoglobin (COHb) level in arterial blood was assayed. The effect of hemoglobin (Hb) on the injured lungs after limb I/R was determined by measuring the changes of lung histology, polymorphonuclear (PMN) count, malondialdehyde (MDA) content and wet-to-dry weight ratio (W/D). Zinc protoporphyrin (ZnPP), an inhibitor of HO, was used to determine whether HO-1 was induced by Hb after lung injury.
Hb led to a significant increase in HO-1 mRNA and protein expression in the lungs, accompanied by the increase of COHb level in arterial blood. Compared with the sham controls, the lung PMN count, MDA content and W/D significantly increased at 4 hours after limb I/R, which reversed by the pretreatment with Hb at 16 hours before reperfusion. ZnPP blocked this protective role of Hb in the injured lungs.
Hb can induce the lung HO-1 expression, which plays an important role in the defense against I/R induced lung injury in rats.
确定血红蛋白（HB）诱导的血红素加氧酶-1（HO-1）在大鼠肢体缺血再灌注（I/R）所致肺损伤中的作用。
用微血管夹夹闭肾下腹主动脉制作大鼠后肢缺血模型，再灌注后发生肺损伤。为诱导肺中HO-1的表达，在再灌注前16小时腹腔注射Hb。采用Northern印迹法和Western印迹法检测肺中HO-1的表达，并测定动脉血中碳氧血红蛋白（COHb）水平。通过测量肺组织学变化、多形核白细胞（PMN）计数、丙二醛（MDA）含量和湿干重比（W/D）来确定血红蛋白（Hb）对肢体I/R后损伤肺的影响。HO的抑制剂锌原卟啉（ZnPP）用于确定肺损伤后HO-1是否由Hb诱导。
Hb导致肺中HO-1 mRNA和蛋白表达显著增加，同时动脉血中COHb水平升高。与假手术对照组相比，肢体I/R后4小时肺PMN计数、MDA含量和W/D显著增加，而再灌注前16小时用Hb预处理可使其逆转。ZnPP阻断了Hb对损伤肺的这种保护作用。
Hb可诱导肺HO-1表达，其在防御大鼠I/R诱导的肺损伤中起重要作用。
