Study of lipids in human amnion and chorion

Epidermal Growth Factor Stimulation of Lecithin Release by Human Amnion

“…On the other hand, surfactant itself stimulates prostaglandins of E type production in human amnion and arachidonic acid content of lecithin could be used for the synthesis of pros taglandins [15]. Accordingly, it had been previously hy pothesized that through the action of a lecithin-cholester ol acyltransferase the arachidonic acid of lecithin could be stored in cholesterol as a nonpolar lipid source for the pro duction of prostaglandins [16]. Based on the above con siderations, EGF-induced lecithin release could, there fore, also be involved in the mechanism of delivery.…”

Betamethasone-Induced Lecithin Release in vitro from the Fetal Membranes

“…In addition, the amnion appears to be more active and more responsive to the ste roid compared to the chorion. Studies on the lipid composition of fetal membranes revealed that the chorion contains higher amounts of phospholipids than the amnion: however, lecithin repre sents 46.3% of amnionic phospholipids and only 16.1 % of phospholipids in the chorion [ 10],…”

“…The sources of arachidonic acid for the synthe sis of the prostaglandins necessary for the onset of labor seem to be mainly represented by phosphatidylinositol as well as by phosphatidylethanolamine [13]. However, it has been hypothesized that through the action of a leci thin-cholesterol acyltransferase the arachidonic acid of lecithin could be stored in cholesterol, as a nonpolar lipid source for the production of prostaglandins [10], On the other hand, phosphatidylcholine also represents about 80% of the surfactant phospholipid fraction, and approxi mately 60% of the phosphatidylcholines are saturated. This saturated phosphatidylcholine is largely dipalmitoylphosphatidylcholine [14].…”

“…The lipid composition of the fetal membranes as well as the turnover of lipids and membrane phospholipids in the amnion are well characterized [10][11][12], In particular, lecithin has been demonstrated to be the major phospho lipid in the amnion, but it is not so abundant in the cho rion [10. 11].…”