银杏叶提取物对在体缺血保存再灌注后肺组织ICAM-1和P-选择素基因mRNA表达的影响

The Study of the Protective Mechanism of Molecular Biology of Ginkgo Biloba Extract on Lung Tissue After Ischemic Reperfusion

目的探讨银杏叶提取物对在体缺血冷藏再灌注后肺组织ICAM-1和P选择素基因mRNA表达的影响。方法新西兰白兔30只,随机分为3组:对照组、LPD组和GBE组。建立兔在体缺血冷藏再灌注模型,对照组左肺不灌注肺保护液,阻断左肺门后直接将左肺下叶载体冷藏于10℃肺保存器内2h,再灌注2h;LPD组左肺门阻断后经肺动脉灌注LPD液,余同对照组;GBE组灌注液为含银杏叶提取物(GinkgoBilobaExtract,GBE)的LPD液,余同LPD组。分别于左肺门阻断前、缺血2h、再灌注2h取左肺组织,RT-PCR技术检测P-选择素和ICAM-1基因mR-NA的表达;免疫组化技术检测P-选择素和ICAM-1基因蛋白质产物量。结果三组在缺血前及缺血2h再灌注前P-selectin基因mRNA表达量及其蛋白质产物免疫组化评分组间均未有显著性差异。再灌注2h后,GBE组P-selectin基因mRNA表达量及其蛋白质产物免疫组化评分显著低于LPD组和对照组。缺血前,所有三组ICAM-1基因mRNA表达量均未有显著性差异。在缺血2h后再灌注前及再灌注2h后,ICAM-1基因mRNA表达量及其蛋白质产物免疫组化评分在GBE组均显著低于对照组和LPD组。结论银杏叶提取物可抑制P-selectin和ICAM-1基因mRNA的表达上调,使肺组织P-selectin和细胞间粘附分子-1蛋白产物减少,从而减轻保存肺的缺血再灌注损伤。银杏叶提取物作为肺保护液添加剂,在进一步研究后可以试用于临床肺移植,为中药提取物的开发应用展示了光明的前景。

Objective Using Rabbit in situ lung ischemia,reperfusion model to explore the mechanism of molecular biology of GBE on the mRNA expression of P-selectin and intercellular adhesive molecule 1 （ICAM-1） on the ischemic lung tissue so as to provide the theoretic basis for the exploiture of new lung preservation solution. Methods Thirty New Zealand white Rabbits were randomly divided into 3 groups： control group,LPD group and GBE group. Rabbit in situ lung ischemia,pulmonary infusion, cold storage and reperfusion model was established, In control group,the left lower lung lobe was stored at 10 centigrade in a specially made lung preservation container for two hours and without lung preservation solution perfusion reperfused for another 2 hours. In LPD group and GBE group,the left lower lobe was perfused with LPD solution and GBE contained LPD solution, respectively after left lung hilus was clamped and the preservation solution was drained via the catheter in the left inferior pulmonary vein. The other procedures were the same as that of control group. The specimens were harvested at pre-clamping lung hilus,2 hours after clamping and 2 hours after reperfusion. The mRNA expression of ICAM-1 and P-selectin in the lung tissue was detected by RT-PCR technique. The expression of ICAM-1 and P-selectin protein was detected by immunochemistry technique. Results There was no significant difference of P-selectin mRNA expression and in the lung tissue among the three groups before ischemia and 2 hours after ischemia,respectively. At 2 hours after reperfusion, the P-selectin mRNA expression in GBE group was significantly lower than that in LPD group and control group respectively. There was no significant difference of the immunohistochemistry score of the expression of P - selectin protein among the three groups before ischemia and 2 hours after ischemia. At 2 hours after reperfusion,the immunohistochemistry score of the expression of P-selectin protein in GBE group was significantly lower than that in LPD group and GBE group, respectively. There was no significant difference of the content of ICAM-1 mRNA among the three groups before ischemia. At 2 hours after ischemia,it was significantly lower in GBE group than that in control group and LPD group,respectively. At 2 hours after reperfusion,the content of ICAM-1 mRNA in GBE group was significantly lower than that in control group and LPD group, respectively. There was no significant difference of the immunohistochemistry score＇of t.he expression of ICAM-1 protein among the three groups before ischemia. At 2 hours after ischemia and 2. hours after reperfusion,the immunohistochemistry score of the expression of ICAM-1 protein in GBE group was significantly lower than that in LPD group and GBE group,respectively. Conclusions Ginkgo biloba extract can inhibit the up-regulation of the mRNA expression of P-selectin and intercellular adhesive molecule-1 in the lung tissue after ischemia reperfusion and inhibit the increase of their protein products of P-selectin and intercellular adhesive molecule-1, so it can reduce the lung ischemia reperfusion injury using the perfusion of LPD solution with the addition of Ginkgo biloba extract. The Ginkgo biloba extract can be applied to the clinical lung transplantation after further investigation. It has given us a bright future of development of medicinal herbs.