Ureteral type

Casts are important components in urine sediment, and their appearance often indicates substantial renal damage. It is a cylindrical structure formed by the coagulation of protein in urine in the renal tubules and collecting ducts, so it is also called a cylinder. The formation of a cast requires proteinuria, and its matrix is ​​the Tamm-Horsfall glycoprotein. In 1966, Mcqueen further confirmed by fluorescent antibody method that various proteins with different molecular weights in the plasma could be aggregated in the form of particles on a transparent tube matrix. In pathological conditions, due to the increased permeability of the glomerular basement membrane, a large amount of protein enters the renal tubules from the glomerulus. In the distal renal tubules and collecting ducts, due to concentration (water absorption) acidification (increased acidity) and cartilage In the presence of sulphate sulfate, the protein aggregates, precipitates, and forms a cast in the small cavity of the kidney.