抄録
The tissue localization of a biliary plasminogen activator, Bilokinase (BK) has been demonstrated mainly in hepatic cells, partially in gallbladder mucosa and blood vessel walls, by using immunofluorolecent technique, suggesting that BK is hepatic origin (Blood & Vessel, 15, 298, 1984). In the present investigation the fibrinolytic activity of cultured hepatic cells was observed by fibrinolysis autograph according to the Todd method and the fibrinolytic activity released into the culture medium was measured by the fibrin plate method of Astrup. Some of the enzymatic and proteinchemical properties of the PA from hepatic cells were also studied. The following conclusions were obtained; 1) The cultured rat hepatic cells produced plasminogen activator (PA) and released it into culture medium. 2) The molecular weight of this PA was determined to be 57, 000. The isoelectric points were determined to be 7.3, 8.0 and 8.2. 3) The affinity of this PA to fibrin was high in contrast to the low affinity to fibrinogen. 4) Since the above enzymatic and proteinchemical properties of the hepatic cell PA resemble those of BK, BK is considered to be of hepatic cell origin.
