Basic Investigations Changes of lipocalin-type prostaglandin D synthase level during pregnancy.

Prostaglandin D (PGD), synthesized by lipocalin-type prostaglandin D synthase (L-PGDS), has marked effects on a number of biological processes, including the prevention of platelet aggregation and the relaxation of vascular smooth muscle. The aim of the study presented here was to examine the significance of L-PGDS in human pregnancy. We measured the concentration of plasma L-PGDS in pregnant and non-pregnant women, and the concentration of L-PGDS in the umbilical cord blood, amniotic fluid and urine of newborns by enzyme-linked immunoabsorbent assay. To determine the localization of L-PGDS, we performed immunohistochemical analysis. To evaluate the usefulness of diagnosis of rupture of membranes (ROM), we determined the concentration of L-PGDS in cervicovaginal secretions. Pregnant women and non-pregnant women had similar L-PGDS concentrations (0.57 ± 0.13 µg/mL vs 0.53 ± 0.07 µg/mL). Umbilical cord blood, amniotic fluid and newborn urine contained higher L-PGDS concentrations (1.87 ± 0.73 µg/mL, 2.62 ± 0.86 µg/mL, 6.31 ± 4.62 µg/mL, respectively) than maternal blood. The concentration of L-PGDS in amniotic fluid from 19 weeks onward was significantly greater than that at 15–18 weeks (3.201 ± 0.384 µg/mL, n = 6 vs 1.735 ± 0.477 µg/mL, n = 4; P < 0.05). Immunohistochemistry revealed that the amniotic cells of the placenta expressed L-PGDS. The sources of L-PGDS in amniotic fluid are fetus urine and amniotic cells. The concentration of L-PGDS in cervicovaginal secretions with rupture of membrane (ROM) were significantly higher than those without ROM. The measurement of L-PGDS in cervicovaginal fluid was useful in the detection of ROM during pregnancy. [ABSTRACT FROM AUTHOR]