Lipopolysaccharide differently affects prostaglandin E 2 levels in fetal and maternal compartments of perfused human term placenta

Abstract

The aim of the present study was to examine the effect of lipopolysaccharide (LPS) on the levels of prostaglandin E 2 (PGE 2) in the perfusates of the fetal and the maternal compartments of perfused human term placental tissue. Term placentas were perfused for 10 h in the absence [control, ( n = 4)] and presence of LPS [LPS = 1 μg/kg perfused placental tissue, ( n = 4)] in the maternal reservoir. Perfusate samples from the fetal and the maternal circulations were collected every 30 min and examined for PGE 2 levels by radio-immunoassay. PGE 2 levels in the fetal circulation were gradually increased reaching significant peak value of 479 ± 159 pg/ml, as compared to PGE 2 levels in the maternal circulation (140 ± 146 pg/ml) ( p < 0.05). After 10 hours of perfusion with control medium, PGE 2 levels in the maternal circulation (347 ± 144 pg/ml) were significantly higher as compared to the fetal circulation (150 ± 57 pg/ml) ( p < 0.05). In presence of LPS, PGE 2 levels in the fetal circulation increased reaching a peak value of 1028 ± 663 pg/ml after 240 min of perfusion. The levels of PGE 2 in the control group after 240 min of perfusion were significantly lower (156 ± 77 pg/ml) ( p < 0.05). No significant differences were detected in the levels of PGE 2 in the perfusate of the maternal compartment in presence of LPS, as compared to control. Our results suggest that the placenta may play an important role in maintaining high levels of PGE 2 in the fetal circulation and low PGE 2 levels in the maternal circulation during normal pregnancy. Moreover, placental PGE 2 release into the fetal and the maternal circulations may be differently affected in presence of intra-uterine infection/inflammation.