Lee J, Malvin R L
Am J Physiol. 1987 Jun;252(6 Pt 2):R1055-8. doi: 10.1152/ajpregu.1987.252.6.R1055.
Although the renal effects of the atrial natriuretic factor (ANF) have been widely investigated, the mechanism of its natriuretic and diuretic effect is still controversial. The purpose of this study was to investigate whether ANF has a specific tubular action distinct from any renal or systemic hemodynamic effects. Renal responses to homologous heart extract (HE) or synthetic ANF were examined in the aglomerular toadfish. A significant natriuresis and diuresis were observed following an intra-arterial injection of either HE (amount derived from 1 heart) or ANF (atriopeptin III, 20 micrograms). However, neither affected urinary excretion of K+. Synthetic ANF did not alter the excretion of Mg2+ or Ca2+. In addition HE showed a hypotensive effect, and ANF did not alter the mean arterial pressure significantly. Neither HE nor ANF affected heart rate. Injection of skeletal muscle extract or saline vehicle alone was without effect on renal function, mean arterial pressure, or heart rate. These results support the hypothesis that ANF has a specific tubular action to increase urinary Na+ and water excretion. The presence of a natriuretic factor was demonstrated in the heart of the fish.
尽管心房利钠因子（ANF）对肾脏的作用已得到广泛研究，但其利钠和利尿作用的机制仍存在争议。本研究的目的是调查ANF是否具有不同于任何肾脏或全身血流动力学效应的特定肾小管作用。在无肾小球的蟾鱼中检测了肾脏对同源心脏提取物（HE）或合成ANF的反应。动脉内注射HE（来自1颗心脏的量）或ANF（心房肽III，20微克）后，观察到显著的利钠和利尿作用。然而，两者均未影响钾的尿排泄。合成ANF未改变镁或钙的排泄。此外，HE显示出降压作用，而ANF未显著改变平均动脉压。HE和ANF均未影响心率。单独注射骨骼肌提取物或生理盐水载体对肾功能、平均动脉压或心率无影响。这些结果支持了ANF具有增加尿钠和水排泄的特定肾小管作用这一假说。在鱼的心脏中证实了利钠因子的存在。
