Protein synthesis by bovine chorion and uterine endometrium during the period of implantation

Abstract

Summary. A grid method for culturing bovine endometrial and chorion tissue is described. A peak of mol. wt 85 000 was obtained only from chorion which had been cultured with intercotyledonary tissue but the co-culture of cotyledon, intercotyledon, kidney or liver with chorion obtained from cows 24\p=n-\29 days pregnant did not significantly alter the overall level of protein synthesis. The addition of progesterone or oestradiol-17\g=b\ to the culture medium (10\m=-\4mol/l) significantly depressed protein synthesis by both chorion and uterine endometrium.

Characterization of Protein Production by Bovine Chorionic and Allantoic Membranes1

“…In the present study, we have demonstrated that both chorion and allantois were active in protein synthesis. These results are in agreement with those of Wathes (1980), who reported that the allantois was more active than chorion in protein synthesis in vitro. We suggest that the allantois contributes to the production of secretory proteins by the conceptus as a whole.…”

Embryo-uterine interactions during early stages of pregnancy in domestic mammals

“…In the pig, co-culture of trophoblast tissue with endometrial explants induced an increase in protein synthesis by the trophoblast, but the effect was only noticeable when the levels of the conceptus proteins were low before co-culture (Rice et al, 1981 ). In similar experiments, Wathes (1980) has not reported any difference in the rate of protein synthesis between co-cultured bovine trophoblast and control tissue. In the same way, culture of Day 11 bovine blastocysts with conditioned media from endometrial explant cultures had no effect on embryonic protein synthesis (Eyestone and French, 1981 ).…”

“…Endometrial explants from the unilaterally gravid horn release more proteins than explants from the non-gravid horn, but the nature of the polypeptides secreted by the endometrium is not different (Basha et al, 1980). However, in the cow, the co-culture of trophoblastic tissues with endometrial explants did not affect protein synthesis by the endometrium (Wathes, 1980 (Guillomot et al, 1987). The trophoblastic factors responsible for such changes were not characterized, but it was shown that a protein (oTP1 : ovine trophoblastic protein 1 ), in sheep, which is secreted by the pre-implantation conceptus, stimulated the synthesis of 6 polypeptides by endometrial explants (Godkin et al, 1984).…”