Cationic excretion by the dog kidney

¹ Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana

The cells of the renal tubules are known to secrete both organic cations and potassium. A method of demonstrating potassium secretion is to force feed a potassium salt for a period of time and then infuse potassium during a clearance experiment. In these experiments the organic cations, tolazoline (Priscoline), N'-methylnicotinamide (NMN) and mepiperphenidol (Darstine) were force fed to dogs. The effects on cationic excretion during standard clearance experiments before and after this procedure indicated an increased efficiency of the renal tubular handling of Priscoline and NMN but not of Darstine. In animals force fed potassium chloride there was also an increased efficiency in the handling of mecamylamine (Inversine). These results add further evidence to the close interrelationship of the transport systems involved in the secretion of potassium and organic cations by the kidney tubules.