Strandberg Jesper, Gade Inger Lise, Palarasah Yaseelan, Gram Jørgen Brodersen, Kristensen Søren Risom, Sidelmann Johannes Jakobsen
Department of Clinical Biochemistry, The Coagulation Unit, Aalborg University Hospital, Aalborg, Denmark.
Department of Haematology and Clinical Cancer Research Centre, Aalborg University Hospital, Aalborg, Denmark.
Res Pract Thromb Haemost. 2023 Mar 13;7(2):100118. doi: 10.1016/j.rpth.2023.100118. eCollection 2023 Feb.
The contact system (CAS) is part of the coagulation system, consisting of a group of plasma proteins stimulating inflammation, coagulation, and fibrinolysis when activated. CAS can be triggered by several activating surfaces, and CAS may play a potential role in thrombus formation. Combined oral contraceptives (COCs) are known to increase the risk of venous thromboembolism, and COCs induce various prothrombotic changes in the coagulation system, whereas the effect of COC on CAS has not been thoroughly investigated.
To investigate CAS in COC users compared with nonusers.
Blood samples from 62 study subjects, 30 COC users, and 32 nonusers, were analyzed. Coagulation factor XII (FXII), prekallikrein (PK), H-Kininogen (HK), cleaved HK (cHK), C1-esterase inhibitor (C1-inh), and the endogenous kallikrein potential (EKP) were measured.
COC users had significantly higher FXII (median, 38.4 vs 28.9 mg/L) and lower C1-inh levels (0.20 vs 0.23 g/L) than nonusers. The levels of PK and HK were not significantly different. Measurement of EKP indicated an increased capacity of CAS in COC users (1860 vs 1500 nmol/L × min), and increased plasma levels of cHK (2.02 vs 1.07 μg/L) indicated an increased activity .
This study demonstrates an increased CAS capacity in women using COC compared with nonusers and also an increased activity . The results indicate that increased contact activation may contribute to the increased thrombotic risk caused by COC.
接触系统（CAS）是凝血系统的一部分，由一组血浆蛋白组成，激活时会刺激炎症、凝血和纤维蛋白溶解。CAS可由多种激活表面触发，可能在血栓形成中发挥潜在作用。已知复方口服避孕药（COC）会增加静脉血栓栓塞的风险，COC会在凝血系统中引起各种促血栓形成变化，而COC对CAS的影响尚未得到充分研究。
比较使用COC的女性与未使用者的CAS情况。
分析了62名研究对象的血样，其中30名COC使用者和32名未使用者。测量了凝血因子XII（FXII）、前激肽释放酶（PK）、H-激肽原（HK）、裂解的HK（cHK）、C1酯酶抑制剂（C1-inh）和内源性激肽释放酶潜力（EKP）。
与未使用者相比，COC使用者的FXII水平显著更高（中位数，38.4对28.9mg/L），C1-inh水平更低（0.20对0.23g/L）。PK和HK水平无显著差异。EKP测量表明COC使用者的CAS能力增强（1860对1500nmol/L×min），cHK血浆水平升高（2.02对1.07μg/L）表明活性增加。
本研究表明，与未使用者相比，使用CO使用COC的女性CAS能力增强，活性也增加。结果表明，接触激活增加可能导致COC引起的血栓形成风险增加。
