The Plasma Proteins in Normal Urine

Abstract

THE first electrophoretic study of the proteins in concentrated normal urine was published in 1951 by Rigas and Heller¹. With the aid of the moving-boundary technique, they demonstrated components with mobilities corresponding to those of the main protein fractions in serum. The albumin/globulin ratio was, however, reversed, and there was a poor separation in the globulin range. Other investigators, using moving-boundary or paper electrophoresis, have reported similar results. I have recently subjected the high molecular substances of normal urine to preparative zone electrophoresis². It was found that all urine protein fractions, including the albumin, contained large amounts of carbohydrate, thus differing in composition from the corresponding plasma fractions. Electrophoretic fractionation, therefore, does not give satisfactory information as to the types and amounts of plasma proteins present in normal urine. Immunochemical methods offer better possibilities for identifying individual plasma proteins in urine. Work on the excretion of plasma proteins in normal human urine by immuno-electrophoresis has been published by Grant³, Patte et al. ⁴, and others. The excretion of about eight different plasma proteins has been demonstrated.