EFFECTS OF 2 ENDOGENOUS NA+,K+-ATPASE INHIBITORS, MARINOBUFAGENIN AND OUABAIN, ON ISOLATED RAT AORTA
EFFECTS OF 2 ENDOGENOUS NA+,K+-ATPASE INHIBITORS, MARINOBUFAGENIN AND OUABAIN, ON ISOLATED RAT AORTA
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DOI：
10.1016/0014-2999(94)00735-p
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发表时间：
1995-02-14
影响因子：
5
通讯作者：
FEDOROVA, OV
中科院分区：
文献类型：
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作者：
BAGROV, AY;ROUKOYATKINA, NI;FEDOROVA, OV
以前，我们报道了蟾蜍毒液中含有Na+，K+- atp酶抑制剂，具有强血管收缩活性。在本研究中，我们用硅凝胶60 F-254+366薄层色谱法从海蟾毒液的类固醇混合物中分离出一种血管活性物质。根据该物质的色谱迁移率和与SbCl3显化后典型的显色反应，我们确定其为先前描述的类固醇，marinobufagenin。在离体大鼠主动脉环上研究了马里诺布费根宁的血管收缩和Na+、K+泵抑制特性，并与瓦巴因进行了比较。瓦巴因（10-100 μ mol.l(-1)）产生微弱的血管收缩，被2 μ mol.l（-1）的酚妥拉明阻断。10 μ mol.l（-1）脲巴因刺激Na+，K+泵，并在较高浓度下抑制。2 μ mol.l（-1）酚妥拉明可消除10 μ mol.l（-1）瓦阿因对Na+，K+泵的激活作用，但不改变高浓度瓦阿因的抑制作用。相比之下，马努布费吉宁引起快速和强烈的血管收缩，并抑制瓦哈因敏感的Rb-86摄取。抗地高辛抗体可拮抗血管收缩剂对马里诺布费格宁的反应，但对沃巴因无拮抗作用。2 μ mol.l（-1）酚妥拉明未改变marinobufagenin的收缩作用。在固相地高辛免疫测定中，marinobufagenin表现出比乌阿班更高的地高辛样免疫反应性。
Previously, we reported that the venom of Bufo marinus toad contains a Na+,K+-ATPase inhibitor with potent vasoconstrictor activity. In the present study, using thin-layer chromatography in Silicagel 60 F-254+366, we separated a vasoactive substance from a mixture of steroids from Bufo marinus venom. Based on chromatographic mobility of this substance and typical color reaction after its vizualization with SbCl3, we identified it as a previously described steroid, marinobufagenin. Vasoconstrictor and Na+,K+ pump inhibitory properties of marinobufagenin were studied in isolated rat aortic rings and compared with those of ouabain. Ouabain (10-100 mu mol.l(-1)) produced weak vasoconstriction, which was blocked by 2 mu mol.l(-1) phentolamine. 10 mu mol.l(-1) ouabain stimulated, and at higher concentrations inhibited, the Na+,K+ pump. 2 mu mol.l(-1) phentolamine abolished the activating effect of 10 mu mol.l(-1) ouabain on the Na+,K+ pump, but did not alter the inhibitory action of higher concentrations of ouabain. By contrast, marunibufagenin elicited rapid and strong vasoconstriction and inhibited ouabain-sensitive Rb-86 uptake. Antidigoxin antibody antagonized the vasoconstrictor responses to marinobufagenin, but not to ouabain. 2 mu mol.l(-1) phentolamine did not alter the constrictor effect of marinobufagenin. In solid-phase digoxin immunoassay, marinobufagenin demonstrated higher digoxin-like immunoreactivity than ouabain.