A stimulatory effect of the fluid from preimplantation rabbit blastocysts upon luteinization of monkey granulosa cell cultures

Abstract

Summary. Blastocyst fluid was aspirated from Day 6\ m=1/ 2\ \ p=n-\ 7rabbit blastocysts and was added to cultures of granulosa cells obtained from preovulatory follicles of untreated rhesus monkeys or from follicles of monkeys treated with PMSG. The stimulation of progesterone secretion was measured and equated with that produced by hCG. The hCG-like activity was also measured in a radioreceptor assay using 125I-labelled hCG and porcine granulosa cells.In 8 out of 10 experiments with cultured cells from untreated monkeys, addition of 20% blastocyst fluid from Days 6\p=n-\9of culture stimulated progesterone secretion by 2\ x =r eq-\ to 6-fold. Similar findings were obtained in 5 experiments with cultures from PMSG\x=req-\ treated monkeys except that the blastocyst fluid was added from Days 0 to 6 of culture. The granulosa cells in such cultures underwent morphological luteinization. Compared to a standard of purified hCG the blastocyst fluid contained about 0\m=.\76\p=n-\2\m=.\5 ng hCG\x=req-\ like activity/ml which was non-dialysable. The radioreceptor assay indicated the presence of 0\ m=. \ 5\ p=n-\ 2\ m=. \ 5 ng hCG-like material/ml.

Relación Útero-Embrionaria Y Su Variación Morfológica Durante El Período Implantacional en Conejo

“…En este punto queda en contacto directo con la mucosa uterina y el embrión ya se ha comenzado a implantar (Grassé, 1958). Varios estudios experimentales sobre el desarrollo de los blastocistos de ratón, conejo y humanos sugieren que en el crecimiento embrionario in vitro resulta anormal (Channing, 1978;Morris, 1983;Hohn, 1989Hohn, , 1992, por lo que la mucosa uterina pasa a ser primordial para el desarrollo embrionario. Carson et al, (2000), en una revisión sobre el estudio implantacional en diversas especies, como roedores, primates, cerdo y conejo, indican que en la mayoría existe un período restringido del ciclo uterino, durante el cual puede ocurrir la implantación.…”

Effects of intrauterine instillation of antiserum to hCG during early pregnancy in mice

“…Human chorionic gonadotrophin (hCG)-like acti¬ vity has been demonstrated in the blastocysts of mice (Wiley 1974;Sengupta et al 1978) and rabbits (Asch et al 1979; Varma et al 1979), employing immunohistochemical techniques and has also been quantitated by radioimmunoassay (Fujimoto et al 1975) and radioreceptor assays (Haour & Saxena 1974). Furthermore, the fluid from rabbit blastocyst has been reported to cause luteinization of granulosa cells from ovarian follicles of monkey, in vitro (Channing et al 1978). It is possible that hCG-like activity present on the pre-implantation embryo may be necessary for its nidation.…”