Okamoto U, Yamamoto J I, Nagamatsu Y, Horie N
Thromb Haemost. 1979 Aug 31;42(2):726-33.
Protease-like activity which split plasminogen-free fibrin was demonstrated in 2 M KSCN extracts of the lung and spleen of conventional rats. The activity was virtually undetectable in tissue extracts from germ-free rats. The extracts from the conventional rat tissues split fibrin and fibrinogen remarkably at neutral pH, but not casein, when examined using fibrin, fibrinogen-agar and casein-agar plates. The fibrinolytic activity was inhibited by STI and DFP, indicating a serine protease nature. The activity was not inhibited by TLCK, t-AMCHA or dansyl-L-arginine-methylpiperidine amide (a selective synthetic thrombin inhibitor, OM189). It was neither activated nor inhibited by cysteine, KCN or iodoacetic acid. The results obtained indicate that the protease-like activity of the lung and spleen extracted with 2 M KSCN from conventional rats has properties which differ from those of trypsin, plasmin, plasminogen-activator, thrombin, and cathepsin A, B and C.
在常规大鼠的肺和脾的2M KSCN提取物中证明了能裂解无纤溶酶原纤维蛋白的类蛋白酶活性。在无菌大鼠的组织提取物中几乎检测不到这种活性。当使用纤维蛋白、纤维蛋白原 - 琼脂和酪蛋白 - 琼脂平板检测时，常规大鼠组织的提取物在中性pH下能显著裂解纤维蛋白和纤维蛋白原，但不能裂解酪蛋白。纤溶活性受到大豆胰蛋白酶抑制剂（STI）和二异丙基氟磷酸（DFP）的抑制，表明其具有丝氨酸蛋白酶的性质。该活性不受甲苯磺酰 - L - 赖氨酸氯甲基酮（TLCK）、反式 - 对氨基甲基环己烷羧酸（t - AMCHA）或丹磺酰 - L - 精氨酸 - 甲基哌啶酰胺（一种选择性合成凝血酶抑制剂，OM189）的抑制。它既不被半胱氨酸、氰化钾或碘乙酸激活也不被其抑制。所得结果表明，用2M KSCN从常规大鼠中提取的肺和脾的类蛋白酶活性具有与胰蛋白酶、纤溶酶、纤溶酶原激活剂、凝血酶以及组织蛋白酶A、B和C不同的特性。
