Effect of phthalate esters on the secretion of prostaglandins (F2α and E2) and oxytocin in cultured bovine ovarian and endometrial cells

The influence of phthalate esters di-2-ethylhexyl phthalate (DEHP) and mono-2-ethylhexyl phthalate (MEHP) on uterine prostaglandin (PGF2α and PGE2) and ovarian oxytocin secretion was investigated. Endometrial, granulosa, and luteal cells from cows on days 8–12 of the estrous cycle were treated with DEHP or MEHP (0.1, 1, or 10 ng/mL). We found that DEHP and MEHP stimulated (P < 0.05) secretion of PGF2α and inhibited (P < 0.001) secretion of PGE2 from endometrial cells. The ratio of PGF2α to PGE2 was markedly altered. The endocrine disrupting chemicals also enhanced secretion of oxytocin (P < 0.05) from ovarian cells. Our results indicated that DEHP and its metabolite MEHP could affect the process of the estrous cycle by impairing secretion of prostaglandin from the uterus and oxytocin from the ovary.