从蟾酥中纯化一种内源性钠泵抑制因子

内源性Ｎａ+ Ｋ+ ＡＴＰ酶 (钠泵 )抑制因子是新发现的一种由肾上腺或下丘脑分泌并贮存的具有生理和病理意义的一种生物活性物质 ,在高血压的发生和发展中可能是重要的因素之一 .内源性钠泵抑制因子与高血压发病关系的研究近年来报道较多 ,已成为该领域国际研究的热点 .Ｈａｍｌｙｎ和Ｈａｕｐｅｒｔ研究组从人的血液及牛的下丘脑中纯化出一种与哇巴因相似的明显抑制钠泵活性的哇巴因样物质(ｏｕａｂａｉｎ ｌｉｋｅｃｏｍｐｏｕｎｄ ,ＯＬＣ) 1 2 ] .Ｓｃｈｏｎｅｒ研究组由牛肾上腺中纯化得到一种分子量为 6 0 0 (ＵＶ 2 5 0ｎｍ)的前…

Purification of an Endogenous Inhibitor of the Sodium Pump from the Toad Venom Chan＇su

An endogenous inhibitor of the sodium pump from the toad venom Chan′su was purified. The dry substance Chan′su was extracted with methanol. The dry residue was passed subsequently through membrane filters with the exclusion size of 10 000, 3 000 and 1 000 at 1 psi in a Filtron Pro Vario-3-System and applied to thin layer chromatography made of Silica 60 F 254+366 separated in CHCl 3∶MeOH∶H 2O. The R f 0.55 fractions inhibiting the sodium pump were purified on a HPLC-RP C18 using a linear H\-2O/methanol gradient at 220 nm and 250 nm on DAD detector. The bio-activity was measured by a specific enzyme-linked immunosorbent assay (ELISA) and 86 Rb-uptake into human red blood cells. In Chan′su there exists an inhibitor of the sodium pump which interacts with antibodies against ouabain and proscillaridin A, and inhibits the sodium pump activity in the red blood cells. The results show that a low molecular weight compound has been isolated from the toad venom Chan′su. It inhibits the sodium pump, interacts preferentially with antibodies against ouabain. It is water soluble and shows a maximum of absorbance at 250 nm. Several milligrams of the compounds from one kilogram were obtained in pure form. The inhibitor differs considerably in its chemical structure from ouabain, because ouabain shows an UV absorbance maximum at 220 nm while the new inhibitor at 250 nm.