ANTIFIBRINOLYTIC ACTIVITIES OF ALPHA-N-ACETYL-L-LYSINE METHYL-ESTER, EPSILON-AMINOCAPROIC ACID, AND TRANEXAMIC ACID - IMPORTANCE OF KRINGLE INTERACTIONS AND ACTIVE-SITE INHIBITION
ANTIFIBRINOLYTIC ACTIVITIES OF ALPHA-N-ACETYL-L-LYSINE METHYL-ESTER, EPSILON-AMINOCAPROIC ACID, AND TRANEXAMIC ACID - IMPORTANCE OF KRINGLE INTERACTIONS AND ACTIVE-SITE INHIBITION
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DOI：
10.1161/01.atv.12.6.708
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发表时间：
1992-06-01
期刊：
影响因子：
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通讯作者：
GONIAS, SL
中科院分区：
文献类型：
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作者：
ANONICK, PK;VASUDEVAN, J;GONIAS, SL
α-N-乙酰基-L-赖氨酸甲酯（NALME）是一种赖氨酸类似物，据报道与纤溶酶（OGEN）和微叠蛋白（OGEN）中的低亲和力赖氨酸结合位点结合。在此处介绍的研究中，我们表明Nalme具有抗纤维蛋白水解活性。但是，与治疗剂Epsilon-Amino-N-核酸（Epsilon-ACA）和曲氨酸酸（TEA）不同，NALME的活性基于抑制纤溶酶活性位点。 NALME（0.1-10 mM）显着抑制纤溶酶，微叠酶素和链蛋白酶酶 - 纤溶酶复合物的amidase酶活性，而不会影响α-凝血酶或组织纤溶酶原激活剂。 Epsilon-ACA和TEA（0.1-10 mm）不影响纤溶酶或微叠素的酰胺酶活性。动力学分析表明，NALME是D-VAL-L-LEU-L-LYS-P-NDROANILIDE HCI（S-2251）水解的竞争性抑制剂。 NALME与纤溶酶的结合完全阻止了S-2251结合。纤溶酶NNME相互作用的K1为0.4 mm。 Epsilon-ACA和TEA抑制纤溶酶和微峰蛋白抑制纤维蛋白单体消化，而无需与任何任一酶的活性位点结合。该结果表明，Epsilon-ACA和TEA通过破坏纤维蛋白单体与纤溶酶和微量蛋白共有的域（可能是Kringle 5）的结构域的非共价缔合来充当抗纤维蛋白分解剂。 NALME抑制纤维蛋白单体消化主要是通过降低amidase活性。纳尔姆（Nalme）是唯一防止碎片X形成的赖氨酸类似物。茶和epsilon-aca主要抑制片段y和D的形成。当与α-2-抗血清素同时孵育纤溶酶和alpha-2-巨糖蛋白和alpha-2-巨糖蛋白时，Epsilon-ACA增加了与alpha-2-2-Mocologloblobloin蛋白反应的纤溶酶的分数； Nalme对纤溶酶分布没有影响。 Epsilon-ACA，TEA和NALME增加了正常血浆的Euglobulin Clot裂解时间。纳尔姆没有延长凝血酶原时间或激活的部分血栓质蛋白时间。这些研究表明，NALME的抗纤维蛋白分解活性是基于纤溶酶活性位点的抑制作用，而Epsilon-Aca和TEA由于Kringle域相互作用而活跃。
Alpha-N-acetyl-L-lysine methyl ester (NALME) is a lysine analogue that reportedly binds to low-affinity lysine binding sites in plasmin(ogen) and miniplasmin(ogen). In the studies presented here, we show that NALME has antifibrinolytic activity; however, unlike the therapeutic agents epsilon-amino-n-caproic acid (epsilon-ACA) and tranexamic acid (TEA), the activity of NALME is based on inhibition of the plasmin active site. NALME (0.1-10 mM) significantly inhibited the amidase activity of plasmin, miniplasmin, and streptokinase-plasmin complex without affecting alpha-thrombin or tissue plasminogen activator. epsilon-ACA and TEA (0.1-10 mM) did not affect the amidase activity of plasmin or miniplasmin. A kinetic analysis showed that NALME is a competitive inhibitor of D-Val-L-LeU-L-Lys-p-nitroanilide HCI (S-2251) hydrolysis by plasmin; NALME binding to plasmin completely prevented S-2251 binding. The K1 for the plasmin-NALME interaction was 0.4 mM. Epsilon-ACA and TEA inhibited fibrin monomer digestion by plasmin and miniplasmin without binding to the active site of either enzyme. This result suggests that epsilon-ACA and TEA function as antifibrinolytics by disrupting the noncovalent association of fibrin monomer with a domain common to both plasmin and miniplasmin (probably kringle 5). NALME inhibited fibrin monomer digestion principally by decreasing amidase activity. NALME was the only lysine analogue that prevented fragment X formation; TEA and epsilon-ACA primarily inhibited the formation of fragments Y and D. When plasmin was incubated simultaneously with alpha-2-antiplasmin and alpha-2-macroglobulin, epsilon-ACA increased the fraction of plasmin reacting with alpha-2-macroglobulin; NALME had no effect on the plasmin distribution. epsilon-ACA, TEA, and NALME increased the euglobulin clot lysis time of normal plasma. NALME did not prolong the prothrombin time or activated partial thromboplastin time. These studies demonstrate that the antifibrinolytic activity of NALME is based on inhibition of the plasmin active site, whereas epsilon-ACA and TEA are active due to kringle domain interactions.