Studies on the prekallikrein-bradykininogen system in liver disease.

The plasma prekallikrein-bradykininogen system was studied in 45 patients with chronic liver disease since its activation with increased liberation of kinin into the plasma could account for some of the clinical manifestations of cirrhosis, namely, vasodilatation, hypotension, and increased capillary permeability.A significant reduction in plasma bradykininogen was found in the cirrhotic patients as compared with control groups of normal subjects and hospital inpatients. The mean plasma prekallikrein was not significantly different and only five patients with liver disease had reduced levels. The most likely explanation for the low plasma bradykininogen was impairment of synthesis by the cirrhotic liver, the usually normal prekallikrein levels making the other possibility of increased activation of bradykininogen to bradykinin in the plasma less likely.