组织型纤溶酶原激活物在急性肺血栓栓塞肺动脉组织中的表达

目的　探讨组织型纤溶酶原激活物 ( t PA)在急性肺血栓栓塞 ( PTE)肺动脉中的表达及意义。方法　 30只家兔随机分组。采用血栓阻塞法制备 PTE动物模型。取材栓塞 3、8和 2 4 h后动物栓塞部位的肺动脉和栓塞远端肺动脉 ;同时设实验对照组 ,取材正常肺动脉。应用免疫组化方法检测肺动脉组织内 t PA的抗原水平。结果　正常肺动脉极少见胞浆棕染的 t PA阳性细胞。栓塞 3h组的栓塞肺动脉和未栓塞肺动脉 t PA阳性细胞数与对照组比较差异没有显著性。栓塞 8h和 2 4 h组肺动脉残存的内皮细胞和平滑肌细胞内均可见明显的胞浆棕染的阳性细胞 ( P均 <0 .0 1)。结论　急性 PTE后可见到栓塞肺动脉 t PA表达增强 ,表明肺具有强大的纤溶潜力 ,这种内源性纤溶活性的增强有利于血栓的溶解

Level of tissue plasminogen activator protein in pulmonary artery in acute pulmonary thromboembolism in rabbit

Objective To study the changes in tissue plasminogen activator(tPA) protein in pulmonary artery and its clinical significance after acute pulmonary thromboembolism (PTE). Methods Thirty rabbits were randomly divided into four groups after replicating a model of acute PTE in rabbit by thrombi occlusion method. Specimens were obtained from both normal and morbid pulmonary artery 3, 8 and 24 hours after APE, and protein contents of tPA were determined using immunohistochemical method. Results A few endothelial cells and smooth muscle cells of the normal pulmonary artery were positive for tPA . After 3 hours of PTE, there was no significant changes in tPA positive stain among embolismic, nonembolismic and normal pulmonary artery. After 8 and 24 hours of PTE, strong positive staining was found in the residual endothelial cells and a part of smooth muscle cells (all P <0 01). Conclusion There is significantly strong positive staining for tPA in the pulmonary artery wall after pulmonary embolism, implying that the local fibrinolysis activity was enhanced, and it might be helpful for lysis of the embolus.