[Changes in the kallikrein-kinin system of the blood during development of experimental myocardial infarct].

Bradikininogen, kallikreinogen, kallikrein, kininase I as well as blood BAEE-esterase and antitryptic activities were studied in development of extensive myocardial infarction in dogs. Some components of kinine system were activated already within 1 hr after ligation of coronary artery, maximal their activation was observed within 3 hrs. In this period content of bradikinin was distinctly decreased--up to 42% of the initial level, kallikrein was activated 8-8-fold, content of kallikreinogen was twice decreased and BAEE esterase activity of blood was increased moderately. Simultaneously, inhibition of kininase I by 30-40% and of antitryptic activity was observed. Gradual normalization of the patterns studied occurred further: kininase I--with 5 days, kallikreinogen, kallikrein and bradikinin--within 10 days of infarction development. Antitryptic activity of blood not only reached normal values but exceeded them within 2 days after the artery ligation. The data obtained suggest the hyperproduction of kinins; the possibility is discussed on the potentiation and prolongation of effect of these physiologically active polypeptides.