Hropot M, Klaus E, Knolle J, König W, Scholz W
Klin Wochenschr. 1986;64 Suppl 6:58-63.
Experiments have been performed in conscious male beagle dogs under maximal water diuresis or hydropenia to determine the effects of synthetic rat atriopeptin III [r-AP III = r-ANF- (103-126)] (Geller et al. 1984), in an intravenous dose of 50 micrograms/kg body weight, on renal function and plasma renin activity. Intravenous injection of r-AP III resulted in an increase in urine and sodium excretion lasting up to 20 minutes, while the glomerular filtration rate and renal plasma flow were hardly influenced under either of the experimental conditions. r-AP III induced an increase in free water clearance from 7.51 +/- 2.45 ml/min in controls to 12.15 +/- 2.25 ml/min in the first clearance period, whereas the free water reabsorption was only slightly reduced (5.56 +/- 1.22 vs. 5.02 +/- 1.23 ml/min). r-AP III caused a slight increase in plasma renin activity from 0.65 +/- 0.46 in controls to 1.02 +/- 0.47 ng X ml-1 X h-1 in water diuretic dogs and from 3.19 +/- 0.51 in controls to 3.72 +/- 0.81 ng X ml-1 X h-1 in hydropenic dogs. These experiments show that the r-AP III-induced salidiuretic response seems not to be mediated by changes in the glomerular filtration rate and renal plasma flow. Moreover, the increase in free water clearance and the absence of change in free water reabsorption indicate a proximal site of action of r-AP III.
在最大水利尿或缺水状态下，对清醒雄性比格犬进行了实验，以确定静脉注射剂量为50微克/千克体重的合成大鼠心房肽IIIr-AP III = r-ANF-(103 - 126)对肾功能和血浆肾素活性的影响。静脉注射r-AP III导致尿量和钠排泄增加，持续长达20分钟，而在两种实验条件下，肾小球滤过率和肾血浆流量几乎未受影响。r-AP III使自由水清除率从对照组的7.51±2.45毫升/分钟增加到第一个清除期的12.15±2.25毫升/分钟，而自由水重吸收仅略有降低(5.56±1.22对5.02±1.23毫升/分钟)。r-AP III使水利尿犬的血浆肾素活性从对照组的0.65±0.46轻微增加到1.02±0.47纳克·毫升⁻¹·小时⁻¹，使缺水犬的血浆肾素活性从对照组的3.19±0.51增加到3.72±0.81纳克·毫升⁻¹·小时⁻¹。这些实验表明，r-AP III诱导的利钠利尿反应似乎不是由肾小球滤过率和肾血浆流量的变化介导的。此外，自由水清除率的增加和自由水重吸收无变化表明r-AP III的作用部位在近端。
