Crambert G, Balzan S, Paci A, Decollogne S, Montali U, Ghione S, Lelièvre L G
Laboratoire de Pharmacologie des Transports Ioniques Membranaires, Hall de Biotechnologies, Universite Paris 7.
Clin Exp Hypertens. 1998 Jul-Aug;20(5-6):669-74. doi: 10.3109/10641969809053244.
An unique endogenous digitalis-like factor (EDLF) has been previously purified from human newborn cord plasma and its differential effects tested on the three well defined functional isoforms (alpha1, alpha2 and alpha3) of the alpha subunits of Na+/K+-ATPase in rat. EDLF specifically inhibits the enzymatic activity. It differs from ouabain by three criteria: a preincubation with the membranes is required for full activity, no effect on the rat cerebral alpha3 isoform and a steep dose-response curve with the same apparent potency for rat alpha2 and alpha1 isoforms of high (10(-7) M) and low affinity (3 x 10(-5) M) for ouabain. These results indicate that the Na+/K+-ATPase inhibitor involved in the regulation of sodium and body fluid volume and present in neonate and adult human plasmas is distinct from ouabain.
一种独特的内源性类洋地黄因子（EDLF）先前已从人类新生儿脐带血浆中纯化出来，并对其在大鼠Na+/K+-ATP酶α亚基的三种明确功能亚型（α1、α2和α3）上的差异效应进行了测试。EDLF特异性抑制酶活性。它在三个方面与哇巴因不同：为达到完全活性需要与膜进行预温育，对大鼠脑α3亚型无影响，以及对哇巴因具有高亲和力（10(-7) M）和低亲和力（3×10(-5) M）的大鼠α2和α1亚型呈现陡峭的剂量反应曲线。这些结果表明，参与钠和体液量调节且存在于新生儿和成人血浆中的Na+/K+-ATP酶抑制剂与哇巴因不同。
