[Characteristics of the kallikreins in healthy and malignant (adenocarcinoma) mucous membrane of the human large intestine].

Total kininogenase activity was higher by 50% in supernatant of malignant mucosa homogenate as compared with normal tissue. But specific kininogenase and N-acetyl-arginine esterase activity were distinctly similar both in normal and tumoral tissues; N-ac-arg esterase activity tended to decrease in malignant mucosa. Partially purified preparations of kallikrein, isolated from adenocarcinoma and normal mucosa of human large intestine, were distinctly identical in their properties: both these enzymes were not inhibited by soybean trypsin inhibitor, they were highly sensitive to main pancreatic inhibitor from bovine tissues (Ki = 10(-10) M) and their molecular mass was about 40,000 daltons. The data obtained suggest that these enzymes may be concerned with tissue kallikreins. Highly purified preparation of kininogenase (85-90% of purity) first obtained from adenocarcinoma of human ascending colon, was identify with tissue kallikreins as it hydrolyzed low molecular kininogen, liberating the kinin--lysyl-bradykinin.