[Assessment of drug nephrotoxicity by the excretion of tubule-specific membrane antigens and enzymes].

A possible tubulotoxicity of drugs can be judged with the help of the excretion of tubular membrane proteins in the urine. The brush border of the proximal tubular epithelia which react particularly sensitive to toxic influences contains surface antigens which easily release themselves from the membrane core membrane under pathological conditions and become provable in the urine by means of biochemical and immunological methods as signs of an early structural cell damage. Apart from these soluble membrane proteins which above all correspond to enzymes such as alanine aminopeptidase and gamma-glutamyl transpeptidase in severe lesions high molecular brush border fragments transformed to vesicles can appear. The clinical relevance of a pathological tissue proteinuria (histuria) of proteins of renal membranes is among others explained at the instance of the renal effects of cytostatics, antibiotics and x-ray contrast medias.