The efficacy of a potassium-rich diet compared to diuretic treatment on the renal elimination of thallium in the rat

Abstract

The influence of potassium retaining diuretic agents (K-canrenoate and triamterene) on the renal elimination of orally ingested thallium (48.9 μmol = 10 mg/kg) in rats proved negligible, whereas in earlier studies we had demonstrated that furosemide significantly enhances the elimination of thallium from the body via the renal route. We could not establish a relationship between the elimination of potassium and thallium on the one hand and between the thalliuresis and the urine production under the influence of diuretic drugs on the other hand. In connection with our interest in the interaction between thallium and alkali-ions like potassium and sodium we also studied the influence of a sodiumrich and a potassium-rich diet on the rate of thallium elimination from the rat's body. When the animals were fed a potassium-rich diet, the amount of thallium excreted in 1 week was increased from 21% of the ingested dose (controls) to 57%. This considerable increase in thallium elimination was not further enhanced by simultaneous treatment with the most potent diuretic furosemide. In the present animal model the treatment with potassium-rich food (approximately 40 mmol KCl · kg−1 · day−1) is superior to the administration of furosemide, with respect to the acceleration of thallium elimination from the body. A sodium-rich diet, however, did not increase the rate of renal elimination of thallium and even inhibited the effect of furosemide in this respect. The mechanism underlying the influence of potassium and sodium on the renal elimination of thallium remains obscure. The relative and absolute amounts of sodium and potassium present in the diet might be of importance with respect to the explanation of species differences observed in the sensitivity towards the effects of thallium and also in the therapy of thallotoxicosis.