STUDIES CONCERNING THE NATURE OF THE SECRETORY ACTIVITY OF THE ISOLATED RINGER-PERFUSED FROG LIVER : I. THE DIFFERENTIAL SECRETION OF PAIRS OF DYESTUFFS

The isolated Ringer-perfused frog liver is able to concentrate in its secretion several hundred or even thousand times a great number of dyestuffs. When two dyestuffs are perfused simultaneously, the liver separates them to a lower or higher degree, some times to such an extent that the secretion of one of them is entirely suppressed by the other. Which one of the two dyestuffs appears prevailingly in the secretion, does not depend upon its diffusibility or lipoid solubility, but perhaps upon its adsorbability. This is concluded from the fact that dyestuffs provided with several (4 to 5) strongly hydrophilic sulfonate groups in their molecule, are not permitted to pass the gland.