环氧化酶2在兔自体移植静脉模型中的表达

Cyclooxygenase-2 expression in rabbit autogenous vein graft models

背景:已经证实移植静脉狭窄远期表现为血管的粥样硬化,而血管的粥样硬化是一种慢性炎症反应的过程。环氧化酶2则是与炎症反应密切相关的酶,其表达程度可能与移植静脉的狭窄相关。目的:观察环氧化酶2在兔自体移植静脉血管中的表达情况。设计、时间及地点:组织形态学水平的动物对照实验,于2007-04/2008-01在解放军第二军医大学长海医院心胸外科实验室完成。材料:选择健康成年新西兰大白兔24只,雌雄不限,体质量2.2～2.5kg。方法:以"cuff"技术建立新西兰大白兔单侧自体颈外静脉-颈总动脉移植模型。主要观察指标:在静脉移植后2,8,12周分别取8只兔,收集移植静脉及对侧颈外静脉作自身对照,以免疫组化及实时定量聚合酶链反应方法检测血管中环氧化酶2表达的差异。结果:免疫组化染色结果显示,正常静脉内膜及中膜薄,由数层细胞排列而成,未见明显环氧化酶2阳性染色。在静脉移植后2,8,12周,各移植静脉内膜及中膜均明显增厚,出现环氧化酶2强阳性染色。在静脉移植后2,8,12周,移植静脉中环氧化酶2mRNA的表达水平均明显高于正常静脉(P<0.01)。结论:环氧化酶2在动脉化的移植静脉血管中出现明显的表达增高。

BACKGROUND： It has been verified that stenosis of grafted vein displayed atherosclerosis, which is a chronic inflammatory reaction. Cycloxygenase 2 is the enzyme closely related to inflammatory reaction. Its expression may be associated with the stenosis of grafted vein. OBJECTIVE： To observe the expression of cyclooxygenase-2 in rabbit vessels following autogenous vein graft. DESIGN, TIME AND SETTING： The histomorphology controlled experiment was performed at the Laboratory of Department of Cardiac and Thoracic Surgery, Changhai Hospital, Second Military Medical University of Chinese PLA from April 2007 to January 2008. MATERIALS： A total of 24 healthy, adult, New Zealand rabbits, of both gender, weighing 2.2 2.5 kg, were selected for this study. METHODS： Models of unilateral external jugular vein-carotid artery autologous transplantation were established by using the cuff＇ technique. MAIN OUTCOME MEASURES： Eight rabbits were obtained at 2, 8 and 12 weeks following vein transplantation. Vein graft and the contralateral external jugular vein samples were harvested as controls. Difference in the expression of cyclooxygenase-2 was measured utilizing immunohistochemistry and real-time （polymerase chain reaction）. RESULTS： Results from immunohistochemistry confirmed that the tunica intima and tunica media of normal veins were thin and composed of many cells. No positive expression of cyclooxygenase-2 was seen. At 2, 8 and 12 weeks following vein transplantation, the tunica intima and tunica media of normal veins became thick, and strong positive expression of cyclooxygenase-2 was found. At 2, 8 and 12 weeks after transplantation, the cyclooxygenase-2 mRNA expression was significantly higher in vein graft compared to the normal veins （P 〈 0.01）. CONCLUSION： Cyclooxygenase-2 expression was increased significantly in the vein grafts.