内源性一氧化碳在大鼠肢体缺血再灌注致远隔多脏器氧化性损伤中的作用

目的　探讨内源性一氧化碳 (CO)在大鼠肢体缺血再灌注 (I/ R)致远隔多器官氧化性损伤中的作用机制。方法　将 6 4只大鼠随机分为 4组 :假手术 (Sham )组 ;Sham 特异性血红素氧化酶阻断剂—锌原卟啉 (Zn PP)组 ;肢体缺血 2小时和再灌注 4小时 (I/ R)组 ;I/ R Zn PP组。测定各组心、肺、肝和肾组织匀浆中丙二醛 (MDA )含量、超氧化物歧化酶 (SOD)活性及血液内碳氧血红蛋白 (COHb)的变化 ,观察动物 2 4小时存活率。结果　与 Sham组相比 ,I/ R组各脏器 MDA含量及血液内 COHb水平均显著增高 ,组织中 SOD活性和动物 2 4小时存活率显著降低 ,有统计学意义(P<0 .0 5 ) ;I/ R Zn PP组与 I/ R组相比各脏器 MDA含量进一步增高 ,血液内 COHb水平、组织中 SOD活性和动物的2 4小时存活率显著降低 ,也有统计学意义 (P<0 .0 5 )。结论　肢体缺血再灌注可导致多器官的氧化性损伤 ,并使 CO产生增多 ,后者在大鼠抗缺血再灌注所致的远隔多器官损伤中具有重要作用。

EFFECT OF ENDOGENOUS CARBON MONOXIDE ON OXIDANT-MEDIATED MULTIPLE ORGAN INJURY FOLLOWING LIMB ISCHEMIA-REPERFUSION IN RATS

Objective To determine the role of endogenous carbon monoxide(CO) in oxidant mediated organ injury following limb ischemia reperfusion (I/R) in rats. Methods Sixty four SD rats were divided into 4 groups: Sham group, Sham zinc protoporphyrin (ZnPP, an inhibitor of heme oxygenase activity), 2 hour ischemia followed by 4 hour reperfusion (I/R) group and I/R ZnPP group. Carboxyhemoglobin (COHb) level in the artery blood, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in the lung, heart, liver and kidney were detected. The 24 hour survival rate of rats was studied. Results Compared with the sham group, the COHb level and MDA content significantly increased, while the SOD activity and the survival rate significantly decreased in I/R group ( P< 0 05). Compared with the I/R group, MDA content significantly increased, while the SOD activity, the 24 hour survival rate and COHb level significantly decreased in I/R ZnPP group ( P< 0 05, respectively). Conclusion Limb I/R could lead to the oxidant mediated multiple organ injury accompanied by the increase of CO level which play an important role in the defense against I/R induced remote multiple organ injury in rats.