Effect of proteinase inhibitor on onset and development of local damage by snake envenomation

本研究的目的是评估蛋白酶抑制剂对蛇毒引起的局部和全身损伤的治疗效果。采用新开发的快速简便的纯化方法，从大鼠血浆中纯化出一种广谱内源性蛋白酶抑制剂——鼠血红蛋白。纯化后的鼠血红蛋白对蛇科5属蛇毒的出血和水肿形成活性均有较强的抑制作用。结果表明，微球蛋白有可能作为局部治疗蛇毒的药物。我们还评估了合成金属蛋白酶抑制剂Ilomastat （GM6001）和CaEDTA对蛇毒出血和凝血活性的抑制能力。结果表明，这两种化合物均能抑制毒血凝血活性，而毒血凝血活性几乎不受鼠血红蛋白的抑制。然而，如果在接种毒液10分钟后局部应用CaEDTA和/或Ilomastat，则不能抑制局部出血和全身凝血功能障碍。如果在中毒一分钟后使用抑制剂，它显示出相当大的抑制局部出血和全身性凝血病的潜力。据推测，局部接种的毒液可以以惊人的速度到达体循环。这可能是蛋白酶抑制剂作用较弱的原因。抑制剂的全身应用和局部应用可能对循环毒素有效。

The aim of the present investigation is to estimate the efficacy, of proteinase inhibitors on treatment of local and systemic damage provoked by snake venom. An intrinsic broad-spectrum proteinase inhibitor, murinoglobulin, was purified from rat plasma employing newly developed rapid and easy purification method. The purified murinoglobulin showed strong inhibitory activity against hemorrhagic and edema forming activities of snake venoms from 5 different genera in Viperidae family. The results showed the possible potential of murinoglobulin as an agent for local treatment of snake envenomation. We also estimated the inhibitory capacity of synthetic metalloproteinase inhibitor, Ilomastat (GM6001) and CaEDTA against snake venom hemorrhagic and coagulation activities. We found that both of compounds inhibited hemorrhagic and coagulation activities of Echis shochureki venom which is the most powerful venom among Viperidae family and hardly inhibited by murinoglobulin. However, local application of CaEDTA and/or Ilomastat failed to inhibit local hemorrhage and systemic coagulopathy if applied those inhibitors 10 min after venom inoculation. In case, the inhibitor was applied one minutes after the envenomation, it showed considerable potential to suppress local hemorrhage and systemic coagulopathy. It is assumed that locally inoculated venom could reach systemic circulation surprisingly fast. It might be the reason for the rather weak potential of proteinase inhibitors. Systemic application of inhibitors as well as local application might be effective on circulating toxins.