Renal tubular reabsorption of protein: demonstration and localization of egg albumin and ß-lactoglobulin reabsorption in the dog

¹ Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania

Using the technique of stop flow analysis, renal tubular reabsorption of egg albumin and ß-lactoglobulin was demonstrated in the dog. The stop flow patterns of these proteins were identical. Both egg albumin and ß-lactoglobulin were shown to be reabsorbed in a proximal part of the nephron overlying the site in which PAH is secreted. Previous studies by stop flow analysis have demonstrated that hemoglobin is reabsorbed in a similar proximal site. These experiments in the intact animal indicate, in agreement with histologic studies, that renal tubular cells have the property of reabsorbing a variety of different types of proteins from glomerular filtrate, and that this property is apparently restricted to cells of the proximal convoluted tubule.