Abstract
Alkaline phosphatase activity of 116 placentas derived from 12 pregnant Sprague-Dawley albino rats was determined by Manning's method in order to evaluate the alteration of enzyme activity in the abnormal pregnancy. This parameter was achieved by studying fetal death (29 cases) resulted from the ligation of the umbilical cord and utero-placental insufficiency developed by the ligation of the uterine blood vessels (34 cases). On the 18 th day of gestation surgery was performed on the rat. Placental alkaline phosphatase activity was determined at the end of 4, 8 and 12 hours after ligation. In the case of fetal death, placental alkaline phosphatase activity remained approximately 94% of the control throughout the experimental period. When the utero-placental circulation was disturbed by ligation, the enzyme activity decreased to 70.5% during the first 12 hour period. This suggests that placental alkaline phosphatase is dependent upon the intrinsic factor of maternal circulation but is less related to the state of the fetus. Therefore it seems possible that the activity of the placental alkaline phosphatase is a sensitive indicator of placental activity.
