DADLE对体外循环后猪肺再灌注损伤的影响

目的探讨δ-阿片受体激动剂DADLE对体外循环(cardiopulmonary bypass,CPB)后肺缺血再灌注损伤的作用及可能机制。方法选取雄性幼猪28只,随机分为四组,即假手术组(S组),体外循环模型组(C组),DADLE预处理组(D组),ATP敏感钾通道阻断剂Glibenclamide同时伍用DADLE预处理组(G组),制作CPB肺缺血再灌注模型,观察气道峰压(peak inspiratory pressure,PIP)、动脉血氧分压(PaO2)、血清中MDA含量、肺光镜下形态学改变。结果CPB前各组间PaO2,PIP,MDA差异无显著意义(P>0.05),再灌注后C组和G组PaO2较CPB前和S组明显降低,PIP较CPB前和S组升高,与D组和S组相比差异有显著意义(P<0.05)。C组与G组再灌注后MDA的含量与CPB前、S组和D组相比明显升高,差异有显著意义(P<0.05),D组再灌注后MDA的升高明显低于C组、G组(P<0.05),虽高于S组但差异无显著意义(P>0.05)。光镜下C组、G组、D组肺组织再灌注后形态学改变较S组明显,但D组形态学改变明显轻于C组、G组。结论DADLE具有减轻CPB后肺再灌注损伤和保护作用。这种作用能部分被Glibenclamide阻断。

Effect of DADLE before Cardiopulmonary Bypass on Ischemia-reperfusion Injury in Pig Lung

Objective To evaluate the effect of [D-AIa2-D-Leu5]-enkephaline (DADLE), a δ-opioid receptor agonist, on pulmonary ischemia-repersion (I-R) injury after cardiopulmonary bypass (CPB), and to evaluate the possible mechanisms concerning the protection of DADLE and the interactions with glibenclamide, a K+ channel closer (ATP-sensitive). MethodsTwenty-eight male pigs were divided into four groups at random (7 pigs per group), i.e. sham operation group (Group S), CPB group (Group C) that was only performed CPB, DADLE pretreatment group (Group D) that received DADLE (1 mg/Kg) before CPB, and glibenclamide group (Group G) that was administered DADLE (1 mg/Kg) and glibenclamide (1 mg/Kg) before CPB. Peak inspiratory pressure (PiP), PaO2 and plasma maleic dialdehyde (MDA) concentration were measured in each group. The histologica1 appearances of the lungs were observed under light microscopy. ResultsThe values of PiP and MDA were significantly lower while that of Pa02 was significantly higher in Group D and Group S than in Group C and G after 60 minutes’ reperfusion (P<0.05). There was a great variety of tissue appearances among the four groups under the light microscope. There was no significantly statistical difference between Group D and Group S, or between Group C and Group G after 60 minutes’ reperfusion except the lung issue appearance under light microscope (P>0.05). ConclusionDADLE pretreatment before CPB can be used to confer a protection against reperfusion injury of lung under normothermia.