Phospholipase C activity and phosphatidylinositol in amniotic fluid. A possible contribution of the fetus to the initiation of human parturition.
We investigated the mutual role between amniotic fluid and fetus in the mechanism of initiating human parturition. Phosphatidylinositol in amniotic fluid began to increase from around 30 weeks to 36 or 37 weeks of gestation and then gradually decreased toward term. On the other hand, we demonstrated phospholipase C activity in amniotic fluid, which increased toward term, and we also demonstrated the high phospholipase C activity in neonatal urine, which was 58-fold higher than that in amniotic fluid. The molecular weight of phospholipase C from neonatal urine was estimated to be 33,000 daltons. It was concluded that the fetus relates to onset of labor by producing arachidonic acid in amniotic fluid by the reaction between phosphatidylinositol from fetal lung and phospholipase C from fetal urine.
Takahashi
H
H
Department of Obstetrics and Gynecology, Akita University School of Medicine, Japan.
Murata
M
M
Maki
M
M
D000649:Amniocentesis; D000653:Amniotic Fluid / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D005333:Fetus / Q000502:physiology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007743:Labor, Obstetric; D010716:Phosphatidylinositols / Q000378:metabolism*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D010738:Type C Phospholipases / Q000378:metabolism* / Q000652:urine
D010716:Phosphatidylinositols; D010738:Type C Phospholipases