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C Le Goascogne

Publications and source records attributed to C Le Goascogne.

32 records · Page 2Linked to original sources
PubMed1984

[Potentiation of the effect of steroid hormones (progesterone and testosterone) inducing the reinitiation of meiosis in Xenopus oocytes in vitro, by inhibitors of phosphatase activity].

The induction of meiosis reinitiation by steroid hormones (progesterone and testosterone) in Xenopus laevis oocytes was studied in vitro in presence of inhibitors of phosphatase activity such as beta-glycerophosphate, considered as a competitive inhibitor, and the two ions, Zn++ and MoO--4. Kinetics of the germinal vesicle breakdown indicating the reinitiation of meiosis, have shown that while these phosphatase inhibitors were not active by themselves under the present experimental conditions, they enhanced the process elicited by progesterone or testosterone.

Alkaline Phosphatase↗
PubMed1983

Induction of germinal vesicle breakdown in Xenopus laevis oocytes: response of denuded oocytes to progesterone and insulin.

Denuded oocytes freed of their vitelline envelope have been prepared by two methods, enzymatically with pronase and manually by microdissection. The response of denuded oocytes to progesterone, in terms of germinal vesicle breakdown (GVBD), was similar to that obtained with defolliculated oocytes (separated with collagenase from follicle cells, but still keeping their vitelline membrane). The same conclusion was drawn with respect to morphological features of the oocyte surface observed by transmission and scanning electron microscopy, before and after progesterone-induced GVBD. The synergistic effect of insulin and progesterone in denuded oocytes was comparable to that observed in defolliculated oocytes. Multiplication stimulating activity (MSA) had the same effect as insulin. These observations indicate that hormones act directly upon oocytes, without interference of the surrounding vitelline envelope and follicle cells.

Animals↗
PubMed1981

A role for prostaglandins in decidualization of the rat uterus.

The deciduogenic action of various kinds of prostaglandin (PG), i.e. PGE1, PGE2, PGF2 alpha and PGI2, methylated prostaglandins (15-met-PGE1, 15-met-PGE2 and 15-met-PGF2 alpha), PGF2 alpha-13-dehydro analogues (13-DH-PGF2 alpha, ent-15-epi-13-DH-PGF2 alpha), endoperoxide analogues (15S)-hydroxy-9 alpha,11 alpha-(epoxymethano)-prosta-5Z,13E-dienoic acid (U 44069) and (15S)-hydroxy-11 alpha,9 alpha-(epoxymethano)-prosta-5Z, 13E-dienoic acid (U 46619), and of the prostaglandin precursor, arachidonic acid, has been demonstrated after intraluminal instillation of these compounds into the uterus of immature rats sensitized with progesterone alone. Under this minimal hormonal stimulation, in which a trauma (a scratch) of the endometrium is required to induce the decidual response, all these compounds elicited the formation of deciduomata, substantiating the suggestion that the scratch-induced decidual reaction is mediated through release of prostaglandin. Confirmation was obtained through the effect of indomethacin and cortisol, both of which decreased the decidual response brought on by a scratch or by arachidonic acid, whereas the effect of PGF2 alpha was decreased by indomethacin but not by cortisol. Histamine, thromboxane B2, and oleic, palmitic and homo-gamma-linolenic acids were not deciduogenic. A dose-dependent inhibitory effect of indomethacin on deciduoma formation by instillation of oil into animals sensitized by progesterone plus oestradiol was also observed. The results support the proposal that the decidual reaction involves prostaglandins and we suggest that the deciduoma is a valuable model for studying the action of prostaglandin-related compounds.

Animals↗
PubMed1978

In vitro decidualization of rat endometrial cells.

Rat endometrial cells were isolated from ovariectomized adults submitted to a progesterone-estradiol sequence proper to sensitize the uterus to respond to a deciduogenic stimulus, and then cultured in vitro in the presence of progesterone. They grew rapidly and became morphologically similar to the decidual cells occurring in vivo with regard to the binucleation and the accumulation of characteristic filamentous material in the cytoplasm. The life-span of the decidualized cells in vitro was comparable to the duration of the deciduoma in vivo. The progesterone treatment of the rat was found to be a prerequisite for such development and transformation of endometrial cells in vitro, since control experiments performed with nonhormonally injected castrated animals gave only isolated islets of epithelial cells and scattered fibroblast-like cells in culture, whereas the decidual transformation was still observed, although with some delay, with cells from progesterone (but not estradiol)-treated spayed rats. Such an in vitro system may provide a new opportunity to study the mechanism of decidualization and of its hormonal control.

Animals↗
PubMed1976

Decidualisation in the prepuberal rat uterus.

Decidualisation has been experimentally induced in the prepuberal rat. It is morphologically similar to that obtained in the adult. The cytodifferentiation includes the formation of binucleated cells and extensive specialised cellular junctions. Furthermore, blastocysts from adults transferred into uterine horns of immature specimens implant and develop, indicating that the decidual response they induce is functionally comparable to the uterine response at the time of nidation in the fertilised adult. The model of the experimental decidual induction in the immature is used to study the ontogenic processes of uterine maturation. Preliminary observations indicate that the 7-10-days period might be of significance in the maturation of the rat uterus.

Age Factors↗