建立静脉血栓栓塞症大鼠模型的研究

目的 建立静脉血栓栓塞症(VTE)大鼠模型.方法 SD大鼠144只,随机分为VTE-A组和VTE-B组,每组72只,分别采用单纯阻滞左股静脉血流和阻滞血流+注入凝血酶0.06 U/kg的方法制备深静脉血栓形成(DVT)模型,观察大鼠患肢肿胀发生率和股静脉血栓阳性率.DVT建模后第1、4、7天,处死2组大鼠各6只,行左股静脉病理学检查;另取2组大鼠各18只,取出左股静脉血栓,注入右股静脉,制备DVT-肺血栓栓塞症(PTE)模型,观察大鼠表现和存活情况.DVT-PTE建模后第1、4、7天分别处死2组大鼠各6只[VTE-A-DnPn和VTE-B-DnPn组],行肺组织病理学检查,计算建模成功率.结果 (1)DVT建模:建模后第1天,VTE-A和VTE-B组大鼠建模成功率均为100%;VTE-B组患肢肿胀发生率[37.5%(27/72)]明显高于VTE-A组[16.7%(12/72),P=0.005].建模后第7天,VTE-B组股静脉血栓阳性率[83.3%(20/24)]明显高于VTE-A组[41.7%(10/24),p=0.003].光镜观察显示建模后第1、4、7天2组大鼠股静脉内分别有红色血栓、混合血栓和机化血栓.(2)DVT-PTE建模:建模后即刻,2组大鼠均出现呼吸急促、心率增快,持续30～60 min后自行缓解.VTE-B-D1P1组大鼠建模后12 h死亡1只,解剖证实为大面积PTE.建模成功率VTE-A-D1PnD4Pn、D7Pn组分别为100%(18/18)、83.3%(15/18)和44.4%(8/18),VTE-B-D1Pn、D4Pn、D7Pn组分别为94.4%(17/18)、100%(18/18)和83.3%(15/18),VTE-B-D7Pn组建模成功率明显高于VTE-A-D7Pn组(P=0.015).光镜观察显示以DVT建模后第4、7天的栓子栓塞肺动脉,血栓溶解性降低.结论 成功建立了制备VTE(DVT-PTE)动物模型的方法.制备DVT模型时从阻滞静脉远端缓慢注入凝血酶可提高VTE建模成功率.

Establishment of rat model of venous thromboembolism

Objective To establish a rat model of venous thromboembolism (VTE). Methods One hundred and forty-four SD rats were randomly divided into 2 equal groups: VTE-A group, undergoing local blocking of left femoral artery with micro vessel clip to cause deep vein thrombosis (DVT), and VTE-B group undergoing local blocking of left femoral artery with micro vessel clip in addition of administration of thrombin slowly injected from the distal end of the femoral vein blocked by micro clip. The rate of swelling limbs was observed. One, 4, and 7 days later 6 rats from each group were killed with their femoral veins taken out to observe the thrombosis rate by light microscopy. Other 18 rats in each group underwent injection of the thrombi from left femoral vein solution in normal saline into the fight femoral vein 1, 4, and 7 days after DVT formation to establish model of DVT-pulmonary thromboembolism (PTE). The 6 rats of each group [VTE-A-DnPn and VTE-B-DnPn groups] were killed 1, 4, and 7 days after DVT-PTE formation respectively with their lungs taken out to observe the rate of PTE by light microscopy. Results ( 1 ) On day 1 after DVT, the successful rate of DVT was 100% in both VTE-A and VTE-B groups, and the swelling limb rate of the VTE-B group was 37.5% (27/72), significantly higher than that of the VTE-A group [ 16.7% (12/72), P =0. 005]. On day 7 after DVT, the positive thrombus rate of the VTE-B group was 83.3% (20/24), significantly higher than that of the VTE-A group [41.7% ( 10/24), P =0.003 ]. One, 4, and 7 days after DVT, there were reddish, mixed, and organized thrombi in both VTE-A and VTE-B groups. (2) Tachypnea and tachycardia occurred immediately and disappeared spontaneously within 30 -60 minutes when solution of thrombi was injected into pulmonary arteries via the right femoral veins. One rat died in the VTE-B-D1P1 group 12 h after the embolization and was anatomically confirmed to suffer from fresh massive emboli lodged in pulmonary arteries. The successful rates of DVT-PTE model were 100% ( 18/18 ), 83. 3% (15/18), and 44.4% (8/18) in the VTE-A-D1Pn, VTE-A-D4Pn, and VTE-A-D7Pn groups respectively, and were 94.4% ( 17/18), 100% ( 18/18), and 83.3% (15/18) in the VTE-B-D1Pn, VTE-B-D4Pn, and VTE-B-D7Pn groups respectively. The successful rate of DVT-PTE model in the VTE-B-D7Pn group was higher than that in the VTE-A-D7Pn group (P =0. 015 ). The thrombi in pulmonary arteries caused by the 4 or 7 days thrombi of DVT showed lower dissolubility in both VTE-A and VTE-B groups. Conclusions A new rat model of VTE (DVT-PTE) has been successfully established. The successful rate of VTE can be increased when thrombin is slowly injected from the distal end of femoral vein blocked by micro clip in addition.