A Comparison of Fibrinolysis of Clots from Venipuncture

止血血凝块的溶解是由一系列复杂的生化途径协调的，并被调节以允许血凝块随着伤口愈合而消失。如果血块溶解得太快，伤口可能会再出血。纤维蛋白溶解的研究传统上集中在通过无创伤静脉穿刺获得的血液上，尽管这样的样品缺乏可能由血管外组织贡献的任何组分，而血管外组织是止血凝块天然存在的地方。因此，我们比较了静脉穿刺获得的血液和手指针刺获得的血液的体外裂解率，手指针刺在出血过程中穿过血管外组织。将凝块孵育2-48小时，并通过测量血清中的蛋白水解分解产物来监测其降解。我们发现手指针刺血凝块溶解速度明显快于静脉穿刺血凝块。我们已经分析了手指针刺和静脉穿刺样本中已知参与纤维蛋白溶解的所有蛋白质，但没有发现两者之间的显着差异。假设基质金属蛋白酶（MMPs）可能有助于手指针刺凝块的溶解，我们分析了手指针刺和静脉穿刺血清中的几种MMPs，发现MMP-9的水平显着高于手指针刺样本。当MMP-9加入指尖血或静脉穿刺血中时，纤维蛋白溶解加速。因此，我们假设MMP-9是在手指针刺血中观察到的更高纤溶率的原因。已经提交了一份手稿。

The lysis of hemostatic blood clots is orchestrated by a complex array of biochemical pathways and regulated to allow the clot to disappear as a wound heals. If a clot dissolves too quickly, the wound may rebleed. The study of fibrinolysis has traditionally focused on blood obtained by atraumatic venipuncture, although such samples lack any components that might be contributed by the extravascular tissue, which is where hemostatic clots naturally exist. Therefore, we have compared the in vitro lysis rate of blood obtained by venipuncture and blood obtained by fingerstick, which passes through extravascular tissue in the process of bleeding. Clots are incubated for 2-48 hours, and their degradation is monitored by measuring proteolytic breakdown products in the serum. We have found that fingerstick clots lyse significantly faster than clots of venipuncture blood. We have assayed fingerstick and venipuncture samples for all the proteins known to be involved in fibrinolysis but have not found significant differences between the two. With the hypothesis that matrix metalloproteinases (MMPs) might be contributing to the lysis of fingerstick clots, we assayed fingerstick and venipuncture serum for several MMPs and found that levels of MMP-9 were significantly greater in fingerstick samples. When MMP-9 was added to fingerstick or venipuncture blood, fibrinolysis was accelerated. Therefore, we are hypothesizing that MMP-9 accounts for the greater rate of fibrinolysis observed in fingerstick blood. A manuscript has been submitted.