Relationship between Serum Concentration and Urinary Output of Trypsin Inhibitor (Hyaluronidase Inhibitor) During Operative Stress

Abstract

The serum concentration and urinary output of trypsin inhibitor was followed in a period before and after operative stress in ten persons. In all subjects the values increased in the postoperative period. No correlation was recorded between the preoperative serum concentrations and urinary trypsin inhibitor outputs, but a highly significant, positive correlation was found between the postoperative increases in serum and urine, demonstrating that the urinary trypsin inhibitor originates from the blood. It is proposed that the urinary trypsin inhibitor is identical with a serum inhibitor which only constitutes a small part of the total trypsin inhibiting activity in serum in the normal state, but whose concentration is markedly increased during stress. The observations could be explained by a passive excretion of the substance in the kidneys, i.e. a glomerular filtration without tubular secretion or reabsorption. The clearance of the compound is estimated to be 0.08 ml per minute (average, for ten persons) but with large individual variations (from 0.02 to 0.12 ml/min) suggesting individual variation in the glomerular permeability to the substance.