Hermes H, Heidenreich O
Arzneimittelforschung. 1985;35(10):1532-5.
The effects of torasemide on renal glomerular and tubular functions were studied in rats using clearance and micropuncture techniques. A dose-response relationship of torasemide in the range of 0.2-20 mg/kg b.w. on the increase of urine volume, urinary sodium and potassium excretion was established. The effect of a dose of 0.2 mg/kg b.w. torasemide was completely abolished by preinjection of 10 mg/kg probenecid, whereas the effects of higher doses remained unchanged. Torasemide had no significant effect on glomerular filtration rate. Proximal fractional reabsorption was not influenced. A remarkable depression of fluid and electrolyte reabsorption, however, occurred in the loop of Henle after torasemide under free flow conditions, as well as in functionally isolated microperfused loops of Henle. No further inhibition of fluid and electrolyte reabsorption between the early distal convoluted tubules and the final urine could be detected. In contrast, a compensatory increase of reabsorption was observed in this part of the nephron. The activity of the tubuloglomerular feedback system was completely and reversibly blocked by torasemide. Torasemide did not differ from other typical loop diuretics with respect to the different renal actions studied here.
利用清除率和微穿刺技术在大鼠中研究了托拉塞米对肾小球和肾小管功能的影响。建立了托拉塞米在0.2 - 20mg/kg体重范围内对尿量增加、尿钠和钾排泄的剂量 - 反应关系。预先注射10mg/kg丙磺舒可完全消除0.2mg/kg体重剂量托拉塞米的作用，而较高剂量的作用保持不变。托拉塞米对肾小球滤过率无显著影响。近端分数重吸收未受影响。然而，在自由流动条件下，托拉塞米给药后髓袢中液体和电解质重吸收明显降低，在功能分离的微灌注髓袢中也是如此。在早期远曲小管和终尿之间未检测到液体和电解质重吸收的进一步抑制。相反，在肾单位的这一部分观察到重吸收的代偿性增加。托拉塞米完全且可逆地阻断了肾小管 - 肾小球反馈系统的活性。就此处研究的不同肾脏作用而言，托拉塞米与其他典型的袢利尿剂没有差异。
