Knauf H, Mutschler E
Medizinische Klinik, St. Bernward-Krankenhaus, Hildesheim, FRG.
Eur J Clin Pharmacol. 1992;43(1):23-7. doi: 10.1007/BF02280749.
The effect of piretanide on Na+ and K+ excretion and on renal haemodynamics has been studied in 14 subjects with a GFR (Inulin clearance) ranging from 140 to 2 ml.min-1. After a two day fluid and salt balance control period, oral piretanide 6 mg induced a natriuresis and kaliuresis, which was proportional to the GFR of the patients. The ratio of drug-induced K+ to Na+ excretion was always 0.13, independent of individual GFR. This was only true for the duration of the action of piretanide, tau, which was 6 h in subjects with normal GFR and 5 h in patients with impaired kidney function. Surprisingly, after tau, i.e. for 24 h after drug administration, less potassium was lost than in the pretreatment period. Neither the GFR nor the renal blood flow (PAH clearance) of the patients were affected by piretanide. In conclusion, piretanide given once a day was an effective natriuretic agent, even in end-stage renal disease, and it produced relatively little K(+)-loss when given once daily.
在14名肾小球滤过率（菊粉清除率）为140至2 ml·min⁻¹的受试者中，研究了吡咯他尼对钠和钾排泄以及肾血流动力学的影响。在为期两天的液体和盐分平衡控制期后，口服6毫克吡咯他尼可引起利钠和利尿作用，且与患者的肾小球滤过率成正比。药物诱导的钾排泄与钠排泄的比值始终为0.13，与个体肾小球滤过率无关。这仅在吡咯他尼的作用持续时间（tau）内成立，在肾小球滤过率正常的受试者中为6小时，在肾功能受损的患者中为5小时。令人惊讶的是，在tau之后，即给药后24小时，钾的丢失量比治疗前期少。患者的肾小球滤过率和肾血流量（对氨基马尿酸清除率）均未受吡咯他尼影响。总之，即使在终末期肾病患者中，每日服用一次吡咯他尼仍是一种有效的利尿药，且每日服用一次时钾丢失相对较少。
