Janicek M J, Van den Abbeele A D, DeSisto W C, Kassis A I, Holman B L, Tumeh S S, Hollenberg N K
Department of Radiology, Harvard Medical School, Boston, Massachusetts.
Invest Radiol. 1991 Jul;26(7):655-9. doi: 10.1097/00004424-199107000-00005.
This study exploits the ability of a collateral arterial network to trap platelet aggregates in order to document the frequency of macroembolization in rabbits after endothelial damage. Two weeks after ligation of the right superficial femoral artery, endothelial injury was induced in the distal aorta; within 3 hours the rabbits were studied using either angiography or 111indium-labeled (111In) platelet scintigraphy. Angiography indicated visible aggregates in the thigh region in eight of 19 and arterial occlusion in three of 19 rabbits. The collateral-dependent thigh also showed more 111In-labeled platelet activity than the contralateral side (P less than .001), whether platelets were injected before or 2 hours after injury. Radioactivity in the limbs of rabbits with no injury was distributed symmetrically. Blood pool volume, assessed with technetium-99m-labeled red blood cells, was the same in both thighs, and could not account for these observations. The findings indicate that platelet activation and aggregation after endothelial injury lead to microembolization much more frequently than it leads to macroaggregate formation and visible artery occlusion.
本研究利用侧支动脉网络捕获血小板聚集体的能力，以记录兔内皮损伤后大栓塞的发生频率。在结扎右侧股浅动脉两周后，对远端主动脉进行内皮损伤；在3小时内，使用血管造影或铟-111（111In）标记的血小板闪烁显像对兔进行研究。血管造影显示，19只兔中有8只在大腿区域可见聚集体，19只兔中有3只出现动脉闭塞。无论血小板是在损伤前还是损伤后2小时注射，依赖侧支循环的大腿区域铟-111标记的血小板活性也高于对侧（P小于0.001）。未受伤兔肢体的放射性分布对称。用锝-99m标记的红细胞评估血池容量，双侧大腿相同，无法解释这些观察结果。研究结果表明，内皮损伤后血小板活化和聚集导致微栓塞的频率远高于导致大聚集体形成和可见动脉闭塞的频率。
