[About degradation products of the inter-alpha-trypsin inhibitor in serum. I. The inter-alpha-trypsin inhibitor as precursor of the acid stable trypsin-plasmin-inhibitor of the serum (author's transl)].

The humoral inter-alpha-trypsin inhibitor is to define as precursor of the acid stable trypsin-plasmin-inhibitor in the serum. The inhibitor is filtrated by the glomerulum and excreted in the urine. The serum level of the inhibitor is increased in nephropathy. Using a new assay for the intact precursor it was found that during inflammation the decreased precursor level indicates an increased turnover, though the glomerular filtration of the acid-stable inhibitor is within normal range. The increase of the precursor level during nephropathy indicates that the kidney is the main degradation organe for the inter-alpha-trypsin inhibitor. Nevertheless, an increase of the acid-stable inhibitor is to be seen. This fact is only to explain if it is assumed that the inter-alpha-trypsin inhibitor is permanently degraded everywhere in the organism.