Expression of prostanoid receptor genes in baboon chorion and decidua during pregnancy and parturition.

The aim of this study was to determine whether expression of prostanoid receptor genes varied with gestational age or labour in the decidua and chorion of baboons. Tissues were obtained at the time of Caesarean hysterectomy in 15 baboons, 10 prior to the onset of labour in the last third of pregnancy and 5 in spontaneous labour at term. Expression of prostanoid receptor genes was determined using Northern blot analysis and the level of expression was related to each of three housekeeping genes. Expression of the genes encoding the EP(1) and FP receptor in decidua and the EP(4) receptor in chorion was lower with advancing gestational age. Expression of the EP(2) receptor gene was lower in labour in decidua, whereas expression of the IP receptor gene was higher in labour in both decidua (twofold) and chorion (fourfold). It is concluded that there is a complex pattern of change in expression of prostanoid receptor genes in chorion and decidua with advancing gestational age and in association with labour. It seems likely that direct effects of prostaglandins on the choriodecidua may have an important role in parturition in the primate.