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D. Martel, M. N. Monier, D. Roche, V. J. De Feo and A. Psychoyos

ABSTRACT

The main objective of the present study was to analyse the hormonal dependence of the metrial gland formed in pseudopregnant animals following massive decidualization. On day 13 of pseudopregnancy (when the metrial gland reaches its maximal development) animals were ovariectomized and given s.c. implants of oestradiol and/or progesterone. A new implant technique for oestradiol delivery is described which provides circulating concentrations of oestradiol in the physiological range.

In addition, we extended our previous work concerning oestradiol receptor and progesterone receptor concentrations in the metrial gland of pseudopregnant rats. The low oestradiol receptor concentration which we previously reported up to day 17 was maintained until the end of pseudopregnancy (day 21–1·5 fmol/μg DNA), whereas the progesterone receptor concentration remained raised (≃3·5 fmol/μg DNA) from day 13 to day 19 and then decreased on day 21.

The correlation of metrial gland weight and kinetics of the tissue oestradiol and progesterone receptors contents with the circulating oestradiol and progesterone concentrations lead to the following conclusions. First, the maintenance of the metrial gland is strictly progesterone-dependent. It is unlike the deciduoma which regresses spontaneously, even in the presence of progesterone. Secondly, the production of oestradiol receptor, but not of progesterone receptor, appears to be repressed in the metrial gland under the influence of progesterone. Thus, the tissue retains its ability to respond to progesterone because of a high concentration of progesterone receptor. It is difficult to attribute this high tissue progesterone receptor concentration to oestradiol stimulation since, even at low levels, oestradiol induces tissue regression. We suggest that the high progesterone receptor concentration could be due to constitutive (basal) progesterone receptor production.

Journal of Endocrinology (1989) 120, 465–472

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D. Martel, R. Frydman, M. Glissant, C. Maggioni, D. Roche and A. Psychoyos

ABSTRACT

The ultrastructure of the luminal surface epithelium was compared in endometrial samples taken from 23 normally cycling women and from 22 patients submitted to ovarian stimulation with clomiphene citrate (100 mg/day for 5 days), human menopausal gonadotrophin (hMG) and human chorionic gonadotrophin (hCG). On day 2 after ovulation, only four out of nine specimens taken from the women in the hormone-treated group were identical to those of normally cycling women. On day 6 after ovulation, only two out of the 13 biopsy specimens from the treated group were the same as those from normally cycling women at that stage. Apical protrusions (pinopodes), typical for this period of the cycle, were missing in 11 of the 13 endometrial samples from the treated group.

These observations suggest that the hormonal treatment applied to induce ovulation (clomiphene citrate, hMG and hCG) can modify the normal development of the prenidatory endometrium, and may thus have a negative effect on the rate of egg implantation.

J. Endocr. (1987) 114, 319–324

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J G LeHoux, A Lefebvre, L Ducharme, J Lehoux, D Martel and N Brière

Abstract

In the current work we studied the effects of a low sodium intake on P450 aldosterone synthase (P450aldo) in the adrenal cortex of male hamsters by Western blotting analysis. We also investigated the zonal distribution of P450aldo with a specific antibody using immunofluorescence and immuno-gold electron microscopy.

Western blotting analysis revealed a progressive induction of P450aldo in the adrenals of hamsters kept on a low sodium diet, with two-, four- and eightfold increases after 2, 4 and 21 days on the diet.

Immunofluorescence microscopy showed that P450aldo was confined to the zona glomerulosa (ZG) cells. Electron microscopy showed P450aldo to be located in the mitochondria of ZG cells. When hamsters were maintained on a low sodium intake for 2, 11 and 21 days, P450aldo was still found only in the ZG; the ZG appeared either unchanged or sometimes slightly enlarged. Moreover, at days 11 and 21, the intensity of the immunofluorescent signal was much stronger in the ZG of hamsters on the low sodium intake than in controls. Hence, immunocytochemistry using the colloidal-gold technique showed P450aldo to be more abundant in the mitochondria of the experimental animals than in controls.

To conclude, P450aldo is present only in the ZG of hamster adrenals and sodium restriction appears to induce its expression by stimulating production within individual ZG cells rather than by stimulating a proliferation of the ZG cells.

Journal of Endocrinology (1996) 149, 341–349