Ludens J H, Clark M A, Kolbasa K P, Hamlyn J M
Upjohn Laboratories, Upjohn Company, Kalamazoo, Michigan 49001-0199.
J Cardiovasc Pharmacol. 1993;22 Suppl 2:S38-41. doi: 10.1097/00005344-199322002-00014.
Previous studies demonstrated that ouabain-like compound (OLC) is widely distributed in mammalian species and is found in a variety of different tissues. Although much evidence suggests that OLC is endogenous to mammals, little information is available concerning physiological and/or pathophysiological roles for OLC. In this study, generic endogenous digitalis-like factor (E-DLF) was measured using an enzyme bioassay and the more specific OLC was determined using ouabain antisera in plasma drawn from dogs before and 30 and 120 min after massive volume expansion with isotonic saline. Plasma OLC was not changed by the saline load, whereas Na excretion was significantly elevated at the 30-min blood draw and remained elevated at the 120-min blood draw. Because renal exposure to OLC did not change with saline loading, it is unlikely that any portion of the profuse natriuresis in these animals could be attributed to OLC. In contrast, plasma E-DLF was higher after the saline load than before in each of four dogs at 30 and 120 min after the infusion. What portion of the profuse natriuresis can be attributed to E-DLF is unknown, although it is reasonable to assume that nanomolar levels of pump inhibitor contributed to the natriuresis to some degree.
以往的研究表明，哇巴因样化合物（OLC）在哺乳动物物种中广泛分布，且存在于多种不同组织中。尽管有大量证据表明OLC是哺乳动物内源性的，但关于OLC的生理和/或病理生理作用的信息却很少。在本研究中，使用酶生物测定法测量了一般内源性洋地黄样因子（E-DLF），并使用哇巴因抗血清在给狗静脉注射等渗盐水进行大量扩容前、扩容后30分钟和120分钟采集的血浆中测定了更具特异性的OLC。血浆OLC并未因盐水负荷而改变，而钠排泄在30分钟采血时显著升高，并在120分钟采血时仍保持升高。由于肾脏对OLC的暴露并未随盐水负荷而改变，因此这些动物大量利钠的任何部分都不太可能归因于OLC。相比之下，在输液后30分钟和120分钟时，四只狗中的每只狗在盐水负荷后的血浆E-DLF均高于负荷前。虽然有理由假设纳摩尔水平的泵抑制剂在某种程度上促成了利钠作用，但大量利钠的哪一部分可归因于E-DLF尚不清楚。
