ESTROGEN SULFATASE ACTIVITY IN ENDOMETRIUM AND FETAL MEMBRANES OF LATE GESTATIONAL AND PARTURIENT COWS

To estimate oestrogen-sulphatase activity in bovine non-caruncular end ometrium, allanto-chorion, allanto-amnion and intact placentomes (desi gnated as placenta), homogenates of these tissues were incubated, usin g oestrone sulphate as a substrate. Tissues had been collected from tw o different groups of animals: during laparotomy in cows on Day 262 of gestation (n=6), and during caesarean section in parturient cows (n=6 ). Sulphatase activity was detected in endometrium, allanto-chorion an d placenta, but not in the allantoamnion. Placental tissue showed a su bstantially higher conversion rate than the endometrium. Only in the p lacenta from parturient animals was sulphatase activity significantly higher than in placentomes obtained on Day 262. It was concluded that in the pregnant cow not only the placenta, but also non-caruncular end ometrium and allanto-chorion have the capability to deconjugate oestro gens, and that an increased sulphatase activity in the placenta at par turition might contribute to the parturient rise of free oestrogens in maternal blood.