Borsodi A D, Bradshaw R A
Thromb Haemost. 1977 Aug 31;38(2):475-85.
The plasma of individuals, hetero- or homozygous for alpha1-antitrypsin deficiency, contains greatly decreased amounts of antithrombin activity as assayed against factor Xa. However, heparin stimulation of the residual antithrombin activity is observed, which is comparable to that of normal plasma. Antithrombins isolated from both normal and alpha1-antitrypsin deficient plasma by a simplified procedure are indistinguishable in both properties and yields. The microheterogeneity observed on isoelectric focusing of both preparations can be eliminated by treatment with neuraminidase. Neither purified human antithrombin nor alpha1-antitrypsin, when assayed against bovine trypsin, is stimulated by heparin. These results clearly establish the unique natures of antithrombin and alpha1-antitrypsin and show that about 75% of the antithrombin activity measured in normal plasma is due to alpha1-antitrypsin. Estimates of antithrombin III activity in normal plasma by assays dependent on enzymatic activity can probably be obtained only in the presence of heparin.
α1抗胰蛋白酶缺乏症的杂合子或纯合子个体的血浆，针对因子Xa进行检测时，其抗凝血酶活性大幅降低。然而，观察到残留抗凝血酶活性受肝素刺激，这与正常血浆相当。通过简化程序从正常和α1抗胰蛋白酶缺乏血浆中分离出的抗凝血酶在性质和产量上均无差异。两种制剂在等电聚焦时观察到的微异质性可通过神经氨酸酶处理消除。当针对牛胰蛋白酶进行检测时，纯化的人抗凝血酶和α1抗胰蛋白酶均不受肝素刺激。这些结果清楚地确立了抗凝血酶和α1抗胰蛋白酶的独特性质，并表明正常血浆中测得的约75%的抗凝血酶活性归因于α1抗胰蛋白酶。通过依赖酶活性的检测方法估计正常血浆中的抗凝血酶III活性，可能仅在有肝素存在的情况下才能获得。
