Gitel S N, Wessler S, Medina V M
Circ Res. 1977 Aug;41(2):187-91. doi: 10.1161/01.res.41.2.187.
When activated factor X (Xa) inhibitory activity of serially diluted human and rabbit plasma is determined in a low salt assay, a lineare plot is obtained for human, but not for rabbit plasma. When a high salt assay is used, the dilution curves for both human and rabbit plasma are linear, and qualititive as well as quantitative differences are essentially eliminated. On Sephadex G-200 chromatography Xa inhibitory activity of human and rabbit plasma appears in two peaks. With the low salt assay the first and second peaks for human plasma contain respectively 30%, and 70% of the activity; whereas with rabbit plasma these values are greater than 95% and less than 5% of the activity. With the high salt assay the figures for human plasma are less than 5% and greater than 95%, and with rabbit plasma 65 +/- 3% and 35 +/- 3%, respectively. With the high salt system, rabbit plasma shows a continuous increase in Xa inhibitory activity with increasing heparin concentrations, similar to that obtained with human plasma. In the high salt system the relative contributions of antithrombin III to Xa neutralization in human and rabbit plasma are different. However, in experiments in which Xa inhibitory activity of antithrombin III is altered by heparin, a simple formula, Total activity (%) = 65% + 0.35 x human plasma (%), permits translation of rabbit data on the Xa-antithrombin III-heparin reaction to man. On the basis of these findings, the rabbit model can effectively be used to study the Xa-antithrombin III reaction.
在低盐检测中测定系列稀释的人血浆和兔血浆的活化因子X（Xa）抑制活性时，人血浆可得到线性图，而兔血浆则不然。当采用高盐检测时，人血浆和兔血浆的稀释曲线均为线性，且定性和定量差异基本消除。在Sephadex G - 200色谱上，人血浆和兔血浆的Xa抑制活性出现两个峰。采用低盐检测时，人血浆的第一个峰和第二个峰分别含有30%和70%的活性；而兔血浆的这些值分别大于95%和小于5%。采用高盐检测时，人血浆的这些数值分别小于5%和大于95%，兔血浆则分别为65±3%和35±3%。在高盐系统中，兔血浆随着肝素浓度增加，Xa抑制活性持续增加，类似于人血浆的情况。在高盐系统中，抗凝血酶III对人血浆和兔血浆中Xa中和的相对贡献不同。然而，在抗凝血酶III的Xa抑制活性因肝素而改变的实验中，一个简单的公式“总活性（%） = 65% + 0.35×人血浆（%）”，可将兔血浆中关于Xa - 抗凝血酶III - 肝素反应的数据转换用于人。基于这些发现，兔模型可有效地用于研究Xa - 抗凝血酶III反应。
