Raised level of amniotic endothelin in pregnancies with fetal aneuploidy.

Amniotic fluid endothelin-1 (ET-1) levels were measured in 38 euploid and in 15 aneuploid pregnancies in the 17th gestational week. Varying distribution of the peptide levels was found in the two groups, with higher values in the pathological cases. Should this finding be confirmed in maternal blood, ET-1 could represent a further analyte to be used in prenatal screening for aneuploidy.

Modulation of amnionic adenylate cyclase and cAMP phosphodiesterase by prostaglandins E1 and F2 alpha.

The action of prostaglandins E1 and F2 alpha on adenylate cyclase and cAMP phosphodiesterase was assayed in cell membrane fractions of amnion obtained before and after labor from term physiological pregnancies. Both prostaglandins stimulate the activity of adenylate cyclase in a dose-dependent manner. After spontaneous delivery both prostaglandins stimulate the activity of phosphodiesterase at lower doses and inhibit it at higher ones while the stimulatory effect of low doses is missing before labor.

Betamethasone-induced lecithin release in vitro from the fetal membranes.

Lecithin release from fetal membranes and placental tissue was assayed in basal conditions as well as under betamethasone administration. In the absence of the steroid, amnion and chorion released lecithin as a function of incubation time. Both tissues responded to betamethasone by increasing the lecithin release, the amnion exhibited a higher basal level and a greater responsiveness to the hormone than the chorion.