放射性血栓致急性肺血栓栓塞症动物模型的建立

目的　利用99mTc 硫胶体 (99mTc SC)制备放射性血栓栓子 ,建立犬肺血栓栓塞症 (PTE)模型 ,观察体内血栓动态演变情况 ,以及溶栓治疗方法的效果。方法　应用99mTc SC加入人全血中制备放射性血栓 ,通过洗脱实验等方法评价核素在血栓中的稳定性和均匀性 ;动物实验采用自体放射性栓子经犬的股静脉注入建立的PTE模型 ,对模型显像观察 14h ,利用核医学的感兴趣区 (ROI)技术以及离体方法测定栓子的自发溶栓率。结果　体外实验表明 :放射性栓子经浸泡洗脱 ,不易将99mTc SC从血栓中析出 ;核素在血栓中的分布较均匀。利用ROI技术测定模型的自发溶栓率为 (6 2± 4 0 ) % ,离体方法为 (6 0± 2 7) %。结论　99mTc SC在血栓中很稳定 ,分布较均匀 ;应用这种放射性栓子可建立观察溶栓效果的急性PTE模型

A canine model of acute pulmonary thromboembolism induced by autologous radioactive blood clots

OBJECTIVE: To establish a canine model of pulmonary thromboembolism (PTE) for evaluating the effects of thrombolytic therapy. METHODS: The preparations of radioactive blood clots in vitro were made from fresh whole blood (from 6 donors) mixed with (99m)Tc-SC. After eluting the clots with saline solution, the stability and evenness of (99m)Tc-SC in the clots were determined. Then a canine model of PTE induced by these clots was established and the rates of spontaneous lysis were measured by the regions of interest (ROI) technique and the in vitro method. RESULTS: (99m)Tc-SC was stable in the radioactive blood clots after elution, and the radioactivities in the thrombi were well-distributed. The rates of thrombolysis were (6.2 +/- 4.0)% as measured by ROI and (6.0 +/- 2.7)% by the in vitro method. CONCLUSIONS: (99m)Tc-SC is stable and well-distributed in blood clots. A canine model of PTE can be induced by autologous radioactive blood clots.