Activity and expression of 15-hydroxyprostaglandin dehydrogenase in cultured chorionic trophoblast and villous trophoblast cells and in chorionic explants at term with and without spontaneous labor

OBJECTIVE: The aim of this study was to investigate whether any changes occ urred at term before and with labor in the 15-hydroxyprostaglandin dehydrog enase messenger ribonucleic acid level and in the 15-hydroxyprostaglandin d ehydrogenase activity in cultured chorionic and villous trophoblast cells a nd in chorionic explants. STUDY DESIGN: Twelve placentas (labor group [vaginal delivery], n = 6; noni abor group [elective cesarean delivery], n = 6) were collected. Chorionic t rophoblast and villous trophoblast cells and chorionic disks were obtained, cultured, and incubated with 282-nmol/L prostaglandin F-2 alpha. Medium wa s collected to measure the 13,14-dihydro-15-keto metabolite of prostaglandi n F-2 alpha, and the cells and disks were snap-frozen to quantify 15-hydrox yprostaglandin dehydrogenase messenger ribonucleic acid expression by North ern blot analysis. RESULTS: The formation of the 13,14-dihydro-15-keto metabolite of prostagla ndin F-2 alpha was significantly lower in the labor group than in the nonla bor group for both sets of cultured cells and for chorionic explants. 15-Hy droxyprostaglandin dehydrogenase messenger ribonucleic acid expression was lower in the chorionic trophoblast cells and chorionic disks of the labor g roup than those of the nonlabor group. However, the 15-hydroxyprostaglandin dehydrogenase messenger ribonucleic acid level in the villous trophoblast cells did not differ between the labor and nonlabor groups. CONCLUSION: Prostaglandin metabolic activity in the chorion is reduced sign ificantly at the time of labor.