右美托咪定预处理对大鼠肢体缺血再灌注肺损伤时脂质过氧化的影响

Influence of pretreatment with dexmedetomidine on lipid peroxidation during limb ischemia-reperfusion lung injury

目的探讨右美托咪定预处理对大鼠肢体缺血再灌注肺损伤时脂质过氧化反应的影响。方法 30只Wister雄性大鼠随机分成3组:假手术组(C组),肢体缺血再灌注组(M组),右美托咪定组(P组)。大鼠肢体缺血再灌注后肺损伤模型建立后,P组大鼠于缺血前30 min经尾静脉给予25μg/kg体重右美托咪定,其余两组给予相同容量的生理盐水。各组于再灌注末行血气分析,观察肺组织病理学变化,测定肺组织湿/干重比(W/D),测定肺组织中丙二醛(MDA)的含量和超氧化物歧化酶(SOD)活性。结果与C组比较,M组和P组均出现肺损伤;PaO2和SOD活性降低;W/D及MDA含量升高(P<0.05);与M组比较,P组肺组织损伤明显减轻;PaO2和SOD活性升高,W/D及MDA含量降低(P<0.05)。结论右美托咪定预处理可抑制肢体缺血再灌注肺损伤大鼠脂质过氧化反应而发挥肺保护作用。

Objective To investigate influence of pretreatment with dexmedetomidine on lipid peroxidation during limb ischemia-reperfusion lung injury. Methods This study collected 30 Wistar rats and randomly divided them into 3 groups （10/each group）：sham operation （C group）, limb IR model group （M group）,dexmedetomidine pretreatment group （P group）. An animal model of ischemia in hind limbs and the reperfusion lung injury was made,afterward,P group received iv dexmedetomidine 25 μg/kg slowly at 30 min before ischemia. In C and M group the animals received equal volumes of NS instead of dexmedetomidine. The all rats were sacrificed at the end of reperfusion and the arterial blood was taken for blood gas analysis. The lungs were immediately removed for pathological examination and determination of the lung Wet/dry weight ratio （W/D）. The values of malondialdehyde（MDA） and superoxide dismutase（SOD） in lung tissues were detected by colorimetry. Results Compared with C group,the damage in lung appeared in M and P group. PaO2 and the activity of SOD was decreased;W/D and MDA content was increased （P＆lt;0.05）;compared with M group,the damage in lung was significantly reduced in P group,PaO2 and the activity of SOD was increased;W/D and MDA content was decreased （P＆lt;0.05）. Conclusion Pretreatment with dexmedetomidine can inhibit lipid peroxidation during limb ischemia-reperfusion lung injury,thus it play a protective role for lung.