Human Placental Transfer of the Prostaglandin Inhibitor Sulindac Using an In Vitro Model

Abstract

Objective: We determined whether the prostaglandin inhibitor sulindac crosses the human placenta.

Methods: The recirculating single-cotyledon placenta model was used to characterize the matenal-to-fetal and fetal-to-maternal transport of ¹⁴C-labeled sulindac in normal term placentas perfused immediately after delivery. Antipyrine was added as a standard for simple diffusion. Serial samples were taken from bth reservoirs during each 3-hour perfusion. Transport was calculated using liquid scitntillation spectrometry for ¹⁴C-labeled sulindac and high-performance liquid chromatography for antipyrine.

Results: There was significant maternal-to-fetal transfer of sulindac. The mean (±SD) transfer at 2 hours was 7.22 ± 2.57%. The fetal-to-maternal transfer was similar at 10.75 ± 3.80%. The mean maternal/fetal concentration ratio of sulindac was 0.42 at 3 hours. Placental uptake ranged from 24-45 ng/g of placenta.

Conclusions: Sulindac crosses the human placenta in small but significant amounts. The transport is similar in both directions, implying simple diffusion.