Renal tubular action of ouabain on Na and K transport during stop-flow and slow-flow technique.

摘要: The renal action of ouabain on reabsorption sodium and secretion potassium was evaluated by stop-flow technique in pentobarbitalized dogs during osmotic diuresis. Ouabain (50 µg/kg) injected directly into the artery to minimize side-effects. In 11 tested, impaired distal Na as reflected inability reduce concentration its normal low value at minimum inflection curve. A ‘slow-flow’ demonstrated that concentrations truly reflect actual developed sites stop-flow. When diuretic urine flow is slowed urethral clamping 0.5 ml/min, there time for low-Na fluid form continually fill entire system including polyethylene catheter. ‘Slow-flow’ are identical those minimum, whether or high after ouabain. sample cut must contain very little contaminating high-Na originating from tubular segments above below true sites. The maximal within 10 min. It decayed exponentially a rate 60% per hour thus reversible manner would allow competitive against aldosterone which augments this site adrenalectomy. The ‘additional proximal reabsorbate’ yields no positive indication impairment. The summit represents occurs so infrequently curve we have insufficient data test action. obliterated 2 3 summits 9 tested. taken represent occurred 6 dogs. elevated drastically 5 these minima suggesting inhibition site.