5-HYDROXYEICOSATETRAENOIC ACID AND HUMAN PARTURITION

5-Hydroxyeicosatetraenoic acid (5-HETE) is an arachidonic acid (AA) me tabolite derived from the lipoxygenase pathway which is capable of ind ucing uterine contractions. The purpose of this study was to determine a). whether 5-HETE concentrations in amniotic fluid increase before o r after the onset of labor and b). whether acetylsalicylic acid (ASA) could modulate the production of 5-HETE by human amnion cells. 5-HETE concentrations are increased in amniotic fluid before the onset of lab or. Furthermore, ASA treatment as expected inhibited PGE(2), but also significantly increased 5-HETE production by amnion cells. 5-HETE conc entrations on average increased by greater than 2.5 fold (p < 0.001) i n amniotic fluid prior to spontaneous labor when compared with samples obtained from the same patients earlier in gestation and therefore ma y be important in mechanisms regulating the onset of labor. ASA provok es an increase in 5-HETE biosynthesis by amnion cells: control media 2 .60 +/- 1.5, ASA treatment alone 5.17 +/- 0.20, IL-1 beta alone 6.39 /- 2.1, and ASA + IL-1 beta 8.95 +/- 1.2 (mean +/- SEM) picograms per microgram protein per 16 hours. These findings may explain in part why cyclooxygenase inhibitors are not always successful in treating women with preterm labor.