Endometrial response to different estrogens

Low dose oestrogen prophylaxis for recurrent urinary tract infections in elderly women

OBJECTIVE

To assess the efficacy of oral oestriol in the prevention of recurrent urinary tract infections in elderly women.

DESIGN

Double-blind, randomised, parallel group, placebo controlled trial

SETTING

Urogynaecology Unit at King's College Hospital with some women recruited from the geriatric units of St. Pancras Hospital and Dulwich Hospital, London (UK).

PARTICIPANTS

Seventy-two postmenopausal women older than 60 years of age (mean 73.2 years) suffering from recurrent urinary tract infections.

INTERVENTION

Oral oestriol (3 mg per day) or placebo for six months. MAIN: outcome measures Urinary tract infection rates.

RESULTS

The study was difficult to conduct because of its design and the age of the participants. Oral oestriol (3 mg per day) was not shown to be superior to placebo in the prevention of recurrent urinary tract infections, but both oestriol and placebo improved urinary symptoms during the trial.

CONCLUSION

The power of the study might have been too low to detect a significant difference between the groups, or oral oestriol (3 mg per day) may have been either the wrong dose or the wrong route of administration for this indication.

Oestrogen concentrations in plasma, endometrium, myometrium and vagina of postmenopausal women, and effects of vaginal oestriol (E3) and oestradiol (E2) applications

Oestradiol (E2), oestriol (E3) and oestrone (E1) levels were measured in plasma and endometrium, myometrium and vagina of 29 postmenopausal women who underwent hysterectomy. The influence of vaginal E3, compared to vaginal E2 therapy at a dose one-tenth that of E3 on the basal steroid levels was examined. We found (1) no correlation between basal tissue and plasma concentrations of the oestrogens in untreated postmenopausal women, however, after vaginal E3 therapy we did find a positive correlation between them, (2) E2 to be the oestrogen in the highest basal concentration in endometrium and myometrium as well as in the vagina, (3) higher basal concentrations of all three oestrogens in endometrium compared to myometrium and vagina, (4) a long term (at least 12 h) elevation of the plasma and tissue E3 concentrations after vaginal E3 therapy (0.5 mg per day), (5) no significant changes of the plasma and tissue E2 concentrations after 0.05 mg per day vaginal E2 therapy, measured 12 h after the last application and (6) no signs of a difference between vagina and uterus in uptake and retention of E3 or E2. In conclusion, there was no difference on this level of mechanism of action in vagina and uterus which can account for the supposed vaginotrophicity and non-uterotrophicity observed with E3 but not E2.

Effects of oestriol: preliminary results on receptor kinetics in target tissues of postmenopausal women

This in vivo investigation was done to study the effects of intravaginal oestriol (E3) administration on endometrial, myometrial and vaginal tissue of normal postmenopausal women. All women received intravaginal E3- suppositoria (containing 0.5 mg E3) once a day for 3 weeks prior to hysterectomy. The medication was continued until the day of operation. At the time of operation both uterine and vaginal tissue was obtained. The receptor content in the cytosol was measured by a multiple point-dextran -coated-charcoal assay using [3H]E2 and [3H]ORG-2058 as ligands. The receptor content in the nucleus was measured by incubating purified whole nuclei in 10 nM [3H]E2 for 18 h at 0 degrees C. We have shown that under these conditions there is a total exchange of all occupied receptors. Preliminary data on 4 patients are available. Vaginal cytology clearly showed an increase of the maturation value. Oestrogen receptor concentrations in the cytosol of all three tissues studied were lower than those obtained in untreated women, suggesting nuclear transformation of the receptor as a consequence of treatment. The nuclear E2 receptor levels cannot be compared with normal women yet. Progesterone receptors in endometrial and myometrial cytosol seemed to be higher than those in untreated women, indicating effects of the treatment. In the human, vaginal progesterone receptor cannot be used as a marker for oestrogenic stimulation because only exceptionally could their presence be detected in either treated or untreated women.

The effect of oral estriol succinate therapy on the endometrial morphology in postmenopausal women: the significance of fractionation of the dose

Postmenopausal women were given estriol succinate orally in a daily dose of 4 mg X 2 for 14 days or 4 mg X 2, 8 mg X 1 and 2 mg in the morning + 2 mg at noon + 4 mg in the evening for 4 wk. Each group consisted of 4 women. The effect of the estrogen treatment was estimated by the endometrial curettage samples taken both before and after the hormone treatment. The curettage samples were studied by both light and electron microscopy. The results showed that a treatment period of 4 wk was necessary to obtain any effect. When 8 mg of estriol succinate was given in a single dose only a slight effect was obtained on the endometrium but when the same dose was divided in 2 daily 4 mg parts, the endometrium showed clearly proliferative changes. Thus estriol is able to produce the same endometrial effect as estradiol. Ultrastructurally the hormone treatment caused an increase in the cytoplasm of the endometrial epithelial cells. Also, whorls of cytoplasmic microfilaments often appeared near the nucleus of the cells.

The physiology of the perimenopausal years: a minireview

Selected studies on the physiology of the perimenopausal years and the subtle transitional changes that occur up to the postmenopause are reviewed. Extraovarian sources of estrogen, which must be considered when recommending dosage of replacement therapy, are described. The effects of hormonal therapy on endogenous hormones and the important roles of progesterone and prolactin are highlighted. The collected evidence suggests that (a) the vasomotor disturbance and depression experienced by estrogen-deficient women are not psychosomatic disorders, (b) osteoporosis is preventable if estrogen therapy is initiated soon after cessation of ovarian function, and (c) administraton of a weak estrogen combined with a progestogen can effectively prevent or treat the difficulties experienced during the female climacteric.

Scanning electron microscopy of the responses of postmenopausal endometrium to treatment with estriol and estriolprogesterone

Seven postmenopausal women are given estriol orally in a daily dose of 1 mg x 2 or 5 mg x 2 for 14 or 28 days and 2 women were sequentially treated with 5 mg x 2 of estriol orally for 21 days, with the addition of 0.2 g x 2 of progesterone rectally in the last 7 days. Three women served as controls. Scanning electron microscopy revealed that the former treatment with estriol was sufficient to produce an estrogen response in the non-ciliated uterine epithelial cells, which developed many long microvilli, sometimes arranged in tufts. The sequential treatment with initial estriol priming followed by estriol and progesterone combined resulted in a slight secretory transformation of the uterine epithelium, observed as an increase in size and number of the apical protrusions of the cells.