Abstract
The activity of C_1 inactivator (C_1 INA), a polyspecific protease inhibitor, which has not been reported in obstetrics was determined to elucidate the etiopathologies of obstetric DIC and pregnancy toxemia, a form of chronic DIC. The animal work was done in rabbits, and the clinical work, on patients with pregnancy toxemia as well as on nonpregnant and pregnant healthy women. The results obtained are as follow ; 1. C_1 INA activity in pregnant rabbits tended to be elevated, as compared to that in non-pregnant rabbits (p<0.05). 2. In rabbits with experimental DIC C_1 INA activity varied with DIC severity. Briefly, it showed little change in mild DIC, but its change became progressively more remarkable with increasing DIC severity. 3. In healthy women, pregnant or not, immunochemical levels of protein were well correlated with C_1 INA activity (r=0.67). 4. In pregnant women C_1 INA activity tended to be depressed. It was lowest in the third trimester of pregnancy, the rate of reduction being 36%. In puerperium, however, it showed a sharp increase. 5. For severe toxemia patients with hypertension as the chief symptom, C_1 INA activity tended to be higher than during the late course of normal pregnancy whereas, for patients with edema as the chief symptom, C_1 INA activity was significantly depressed (p<0.05).
