权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Structural analysis of endogenous digitalis and studies on the role of it in electrolytes and blood pressure control. In particular, studies on a novel substance, marinobufagenin with double hydrogen.

内源性洋地黄的结构分析及其在电解质和血压控制中的作用研究。

基本信息

批准号：
14572191
负责人：
TAKAHASHI Hakuo
金额：
$ 2.24万
依托单位：
Kansai Medical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

Inhibition of sodium-potassium adenosine triphosphatase (Na,K-ATPase) by marinobufagenin (MBG) or telocinobufagin (TCB) are more potent than that of ouabain. We found that those bufadienolides are circulating in human blood, upon analyzing the structure by using multiple steps of liquid chromatography (LC) and mass-spectrometry (LC/MS), nuclear magnetic resonance (NMR). TCB has two more hydrogen than MBG.Plasma concentration of TCB was almost double of MBG, the correlation among them was highly significant. Therefore, we thought that the TCB is hydrolysed to MBG.Since the concentration of TCB is much higher than MBG, TCB was thought to be the cardinal endogenous digitalis. This is the first report to show the existence of TCB in mammalian samples. Furthermore, the concentration was compared in normal subjects and patients with terminal renal failure, and it was almost twice higher in the patient plasma as compared to it in normal subjects. Therefore, both TCB and MBG may be functioning as the physiological regulator of electrolytes and consequently blood pressure.Then, we made monoclonal antibody for TCB, but unfortunately it cross-reacted with MBG too, and enzyme-linked immunosorbent assay (ELISA) was developed. Because this ELISA system was interfered with constituents of plasma, it was useful only for measurement of urine samples. By using this ELISA, effects of sodium-loading was tested in rats, we found that rats with high salt diet excreted more TCB/MBG than in rats with normal diet.

marinobufagenin （MBG）或telocinobufagin （TCB）对钠钾腺苷三磷酸酶（Na， k - atp酶）的抑制作用比瓦巴因更有效。通过液相色谱（LC）、质谱（LC/MS）、核磁共振（NMR）等多步骤分析，发现这些丁二烯内酯在人体血液中循环。TCB比MBG多两个氢。TCB的血药浓度几乎是MBG的两倍，两者之间的相关性非常显著。因此，我们认为TCB被水解成MBG。由于TCB的浓度远高于MBG，因此TCB被认为是主要的内源洋地黄。这是第一份显示哺乳动物样本中存在TCB的报告。此外，将正常受试者和终末期肾功能衰竭患者的血药浓度进行比较，发现患者血浆中的血药浓度几乎是正常受试者的两倍。因此，TCB和MBG可能都是电解质和血压的生理调节剂。然后，我们制备了TCB单克隆抗体，但不幸的是它也与MBG交叉反应，并建立了酶联免疫吸附试验（ELISA）。由于该ELISA系统受到血浆成分的干扰，因此仅适用于尿液样品的测定。采用该酶联免疫吸附试验对大鼠进行了钠负荷试验，结果发现高盐饮食大鼠的TCB/MBG排泄量高于正常饮食大鼠。