The Tamm-Horsfall glycoprotein and the urinary system: Electrophoretic and electron microscopic observations

Abstract Preparations of Tamm-Horsfall glycoprotein, concentrated urine, hom o genates of kidney and exfoliated transitional epithelium of urinary tract of man and sheep, and cell fractions of this epithelium were ele c trophoresed on polyacrylamide gels. Cylinders were stained for proteins with amidoblack B, for lipids with sudan black B and for carbohydrates with PAS and mucicarmine, and further characterized by methylation and neuraminidase digestion. Similar electrophoretic patterns were observed for homogenates of transitional epithelium, plasma membrane of this epithelium and kidney and the Tamm-Horsfall glycoprotein. Electron microscopy revealed fragments of plasma membrane in preparations of Tamm-Horsfall glycoprotein. In these preparations, lipidic phosphorus was chemically detected. It is concluded that the Tamm-Horsfall glycoprotein is closely related to cell surfaces of renal tubular cells and transitional epithelium.