Aldosterone Stimulation of Riboflavin Incorporation into Rat Renal Flavin Coenzymes and the Effect of Inhibition by Riboflavin Analogues on Sodium Reabsorption

• Text
• PDF

Abstract

This study was designed to investigate a possible relationship between the effect of aldosterone upon urinary electrolytes and the incorporation of [14C]riboflavin into renal [14C]flavin mononucleotide (FMN) and [14C]flavin adenine dinucleotide (FAD). Adrenalectomized Sprague-Dawley rats that weighed between 185 and 210 g were pretreated with 15 μg/100 g body wt dexamethasone intraperitoneally. 16 h later they were administered aldosterone (1.5 μg/100 g body wt) and [14C]riboflavin (5.0 μCi/200 g body wt). The urethra of each rat was ligated, and the rats were sacrificed by decapitation 3 h later. The urine was aspirated from the bladders of each rat and analyzed for total Na+ and K+ excretion while the kidneys were removed and the formation of [14C]FMN and [14C]FAD was determined for each kidney. There was a significant increase in the formation of renal [14C]FMN and [14C]FAD (27.3 and 14.4%, respectively) after aldosterone treatment. Aldosterone significantly decreased the excretion of Na+ by 50%, and increased that of K+ by 55%.

Authors

Daniel Trachewsky