Search

Estrogens are synthesized from C19 steroids by a unique form of cytochrome P450 aromatase. Expression of the human CYP19 gene involves tissue specific use of alternative promoters. In the present study, an RT-PCR procedure was used to amplify and quantify various transcripts expressed in human granulosa cells. Cells were aspirated together with follicular fluid from Periovulatory ovarian follicles present in ovaries of 14 patients undergoing a treatment for in vitro fertilization. Sequencing of PCR products demonstrated the presence of exon I.4-specific transcripts in addition to exon P.II, exon I.3 and I.3-truncate transcripts. Quantitative results confirmed that exon P.II specific transcripts were largely predominant compared to other exon-specific transcripts, and that exon I.4-specific transcripts were the least abundant.

Increasing evidence suggests that cytokines may play a role in ovarian processes. The purpose of this study was to determine if interleukin-1 (IL-1) could modulate rabbit pre-ovulatory follicular function and to explore cellular sites of IL-1 biosynthesis in rabbit follicles. Development of rabbit pre-ovulatory follicles was induced by 200 mIU equine chorionic gonadotropin daily for 2 days. Seventy-two hours after the last injection, ovaries were excised and granulosa and theca cells isolated. The two types of cell were pre-incubated for 24 h in Minimum Essential Medium (MEM) with 5% fetal calf serum (FCS), and then incubated for 24 h in MEM with 2.5% FCS with appropriate stimulants. Results showed that rabbit granulosa and theca cell culture supernatants contain IL-1 bioactivity and that this bioactivity was diminished by gonadotropins, FSH and human chorionic gonadotropin, in a dose-dependent manner. Low doses of IL-1 (1 ng/ml) inhibited gonadotropin-induced progesterone production in both cell types and at the same time increased cell numbers. A study of the mechanism of IL-1 action demonstrated that it affects cAMP generation, and also steps distal to cAMP formation. We conclude that in our model gonadotropins, by inhibiting IL-1 production, could control IL-1 modulation of gonadotropin action on steroidogenesis.

Féral C, Le Gall S, Leymarie P. Angiotensin II modulates steroidogenesis in granulosa and theca in the rabbit ovary: its possible involvement in atresia. Eur J Endocrinol 1995;133:747–53. ISSN 0804–4643 Accumulating evidence has shown the ovary of mammals to contain an intrinsic renin–angiotensin system that has been ascribed an autocrine-paracrine role. The present study in the female rabbit ovary investigated the putative in vitro action of angiotensin II (A II) on basal and gonadotropin-induced steroidogenesis. Ovarian follicles from immature female rabbits treated with pregnant mare's serum gonadotropin (PMSG) were dissected out and a complete separation of the theca interna from the granulosa layer was performed, to demonstrate that A II affects separately the two individual cellular components of the follicular wall. We could show that theca is a source of estradiol whose production under human chorionic gonadotropin (hCG) stimulation was reduced by A II. At the same time, A II increased the in vitro hCG-stimulated secretion of testosterone by theca. In granulosa, A II decreased hCG-stimulated aromatization of androstenedione to estradiol but did not alter the release of hCG-stimulated progesterone production. These results suggest that A II could induce locally an increase in follicular fluid androgen/estrogen ratio and possibly participate in causing atresia. C. Féral, EP CNRS 009, Laboratoire de Biochimie, CHU Caen, F-14032 Caen Cedex, France

The usefulness of early second-trimester serum determinations of pregnancy-associated plasma protein A (PAPP-A) and pregnancy-specific beta1-glycoprotein (SP1) in suspected cases of fetal trisomy 18 was examined in a retrospective, cross-sectional study. Maternal serum PAPP-A and SP1 in 20 cases of fetal trisomy 18 between 15 and 20 weeks of pregnancy, and in 40 controls matched for gestational age and storage time were determined and compared with hCG and free oestriol (uE3). In trisomy 18, the reduction in serum concentration was found to be more pronounced for PAPP-A than for hCG and free oestriol. While none of the 40 control sera had a MoM below 0.2 for either PAPP-A, hCG or uE3, in the trisomy 18 group (20 cases) 17 (85 per cent) of the PAPP-A but only 5 (25 per cent) of the hCG and 4 (20 per cent) of the uE3 results were below the 0.2 MoM threshold. SP1 did not distinguish between controls and trisomy 18. This chromosomal abnormality is too rare a condition to justify maternal serum PAPP-A determination in the second trimester as a routine procedure, but such a test can play a useful role whenever the risk of trisomy 18 is found to be only marginally increased after hCG and uE3 measurements.

We report about one case of asymptomatic duplication of the colon, which was diagnosed with a barium enema in an adult. This condition is rare, especially in the tubular form such as described in this case. The discussion is associated to a review of the literature.

Plasma levels of testosterone (T), estrone (E1) and estradiol (E2) have been studied in 115 normal boys 5–19 years old and related to pubertal stages. The significance of pubertal changes is greater for T than for E1 and E2, and the increase of T begins earlier than the increase of E2. Response to HCG, 3 × 1500 IU every other day, has been studied in 61 of these subjects. The increase of testosterone from basal to post-stimulatory levels (ΔT) goes up at the beginning of puberty but does not change further. ΔE1 does not increase significantly during puberty. ΔE2 increases at late puberty. All normal prepubertal boys had a definite response of T to HCG, peak level being at least 1.60 ng/ml. The number of injections of HCG and the duration of the stimulation are more important than the doses injected to obtain maximal Leydig-cell stimulation in prepubertal children.

Corpora lutea from sheep and cows as well as human and primates contain both large and small steroidogenic cells exhibiting distinct functional properties. Only the small cells seem to be able to respond in vitro to LH stimulation by raising their progesterone secretion. However, the entire progesterone secretion of the corpus luteum has been shown to be regulated in vivo by LH in the primate. The LH steroidogenic action involves the activation of membrane adenylate cyclase whose molecular mechanism has been elucidated. Then a rise in intracellular cyclic AMP induces phosphorylation by a cyclic AMP dependent protein kinase of steroidogenic protein targets which have not yet been completely identified. In sheep and cows, luteolysis is believed to be the consequence of a series of reciprocal interactions between the corpus luteum whose large cells secrete pulses of oxytocin in response to PGF2 alpha luteolysin and the endometrium which secretes pulses of PGF2 alpha in response to oxytocin. The secretion of endometrial PGF2 alpha can only begin after the induction of endometrial receptors by estradiol, from the preovulatory follicles. Similarly in women and primates luteolysis, which does not require the presence of the uterus, could be the consequence of local reciprocal paracrine interactions between luteal cells of different types. These interactions are likely to involve PGF2 alpha' oxytocin and estradiol. The biochemical mechanism responsible for the inhibition by PGF alpha of LH induced progesterone secretion in luteal cells could involve a stimulation in the cell membrane of protein kinase C and the rise of cytosolic Ca+.(ABSTRACT TRUNCATED AT 250 WORDS)

The testicular endocrine function was studied in 12 patients aged from 33 to 76 years (mean: 56.3 +/- 11.5 years) presenting with an apparently primary vertebral osteoporosis and in 14 age-matched controls (mean: 52.6 +/- 12.8 years). The mean bone mineral content, measured in the vertebral column by biphoton absorptiometry, was lower in patients than in control (P +/- 0.01). Plasma levels of testosterone, oestradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were the same in both groups. In two patients of each group, a rise of LH with normal testosteronaemia was suggestive of compensated Leydig's cell deficiency. There was no correlation between bone mineral content, plasma testosterone, LH, FSH level and the subjects' weight and height. However, a positive correlation was found between plasma oestradiol level and bone mineral contents in patients with osteoporosis (P +/- 0.01) ans in all subjects under study (P +/- 0.05). This study shows that primary osteoporosis is not due to testicular deficiency and suggests a possible action of oestradiol on male bone.

Plasma hormones have been evaluated from birth to six months in a boy with male pseudohermaphroditism due to congenital 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) deficiency. At birth, plasma 17-hydroxyprogesterone (17-OHP) was slightly elevated while cortisol was within the normal range. Both 17-OHP and testosterone (T) were increased the fifth day. At the age of 2 months, only the baseline level of 17-hydroxypregnenolone (17-OH5P) was slightly elevated and the diagnosis of 3 beta-HSD deficiency was established in view of the excessive response of 17-OH5P and dehydroepiandrosterone (DHA) to Synacthen administration. There was an important increase of T and dihydrotestosterone in response to chorionic gonadotropin (hCG) administration while no significant variation of the other studied steroids was observed. These results suggest that the determination of plasma 17-OH5P seems to be the best tool to diagnose congenital 3 beta-HSD deficiency. The increase of 17-OHP is the result of 17-OH5P conversion in peripheral tissues. Though T response to hCG is rather normal, a partial testicular deficiency of 3 beta-HSD cannot be excluded. The ambiguous genitalia observed in this boy with normal plasma T levels might suggest that T production might have been deficient at the time when urethral-fold fusion occurred.

The effects of oral buspirone (BUS, 10 mg) and diazepam (DZP, 10 mg) were studied in 12 healthy women volunteers using subjective ratings, objective tests of psychomotor and cognitive functions and urinary dosage of catecholamine output. Drugs were randomly administered to the same subjects, in a crossover, double-blind study, each drug administration being separated by at least 1 week. BUS subjective effects were less severe than those of DZP and not accompanied by feelings of sleepiness that characterized DZP sedative effects. Furthermore, BUS did not impair psychomotor functioning while DZP induced both an impairment of central sensory processing and, to a lesser extent, an impairment in delayed memory.

The authors provide a didactic analysis of the errors in perception that can lead to false-negative findings in the detection of advanced rectocolonic cancers with double-contrast enema. They consider 5 categories of images as typical, ie. transverse or horizontal linear opacities, abnormal lumen due to haustral folds on semiaxial views, "pool sign", amputation of the cecum and irregular hypertrophy of the ileocolic valve. These mistakes will become exceptional if the double-contrast images are studied thoroughly using precise rules, and the percentage of false-negative findings in the detection of rectocolonic cancers should thus be reduced to 1%.

Plasma levels of testosterone, estrone and estradiol were measured by radioimmunoassay every 30 min for 25 h in four young adult males. A coincident though unidentical circadian rhythm of plasma testosterone was demonstrated in all cases. Rapid variations which were consistent with a pulsatile pattern of testosterone secretion were seen in each subject. In one of them an identical rhythm was shown again when reinvestigated 3 months later. Plasma estradiol level was constant throughout the day, but the estrone curve exhibited a phase of lower levels during the sleep while testosterone concentration was gradually increasing.