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1.
Endocrinology ; 142(9): 3791-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11517155

RESUMO

It has previously been demonstrated that 19-nor contraceptive progestins undergo in vivo and in vitro enzyme-mediated A-ring double bond hydrogenation. Bioconversion of 19-nor progestins to their corresponding tetrahydro derivatives results in the loss of progestational activity and acquisition of estrogenic activities and binding to the ER. Herein, we report subtype-selective differences in ligand binding and transcriptional potency of nonphenolic synthetic 19-nor derivatives between ER alpha and ER beta. In this study, we have examined both ER- and PR-mediated transcriptional activity of a number of A-ring chemically reduced derivatives of norethisterone and Gestodene. Double bond hydrogenation decreased the transcriptional potency of norethisterone and Gestodene through both PR isoforms with a 100- to 1,000-fold difference, respectively. In terms of the effects of norethisterone and Gestodene and their corresponding 5 alpha-dihydro (5 alpha-norethisterone and 5 alpha-Gestodene), or 3 alpha,5 alpha-tetrahydro or 3 beta,5 alpha-tetrahydro derivatives (3 alpha,5 alpha-norethisterone/3 alpha,5 alpha-Gestodene and 3 beta,5 alpha-norethisterone/3beta,5 alpha-Gestodene, respectively) on estrogen-mediated transcriptional regulation, the 3 beta,5 alpha-tetrahydro derivatives of both norethisterone and Gestodene showed the highest induction when HeLa cells were transiently transfected with an expression vector for ER alpha. This activity could be inhibited with tamoxifen. These compounds did not activate gene transcription via ER beta, and none of them showed antagonistic activities through either ER subtype. The 3 beta,5 alpha-tetrahydro derivatives of both norethisterone and Gestodene were active in other cells in addition to HeLa cells and activated reporter expression through the oxytocin promoter. In summary, two ER alpha selective agonists have been identified. These compounds, with ER alpha vs. ER beta selective agonist activity, may be useful in evaluating the distinct role of these receptors as well as in providing useful insights into ER action.


Assuntos
Progestinas/metabolismo , Receptores de Estrogênio/agonistas , Animais , Células CHO , Cricetinae , Receptor alfa de Estrogênio , Células HeLa , Humanos , Estrutura Molecular , Noretindrona/metabolismo , Noretindrona/farmacologia , Norpregnenos/metabolismo , Norpregnenos/farmacologia , Oxirredução , Receptores de Estrogênio/classificação , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/fisiologia , Ativação Transcricional/fisiologia
2.
J Clin Endocrinol Metab ; 47(4): 812-7, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-122413

RESUMO

A 20-yr-old phenotypical male with a 46, XY chromosome complement, a hernia uteri inguinale, and bilateral anorchia was studied. Eunochoidal body proportions, infantile type of male external genitalia with empty scrotum, underdeveloped sexual characteristics, and delayed bone age suggested the existence of inadequate testicular function. Extremely low levels of circulating testosterone and a lack of response to hCG stimulation was found. Persistently elevated blood levels of LH and FSH with an adequate pituitary response to an iv bolus of synthetic LRH was demonstrated, thus indicating inadequate endocrine gonadal function as well as functional integrity of the hypothalamic-pituitary unit. At the time of an inguinal hernioplasty, a small but well developed uterus was removed. No gonads were found within the true pelvis, inguinal canals, or along the anatomical pathways of testicular descent. A cord-like structure found in the left inguinal canal contained only fibrous tissue without gonadal elements. It is proposed that the occurrence of two altered events during embryogenesis, failure of Müllerian duct regression and late testicular regression, may explain the underlying defect in this unusual abnormality of sexual differentiation.


Assuntos
Transtornos do Desenvolvimento Sexual/patologia , Disgenesia Gonadal/patologia , Ductos Paramesonéfricos/patologia , Testículo/anormalidades , Adulto , Gonadotropina Coriônica , Transtornos do Desenvolvimento Sexual/sangue , Transtornos do Desenvolvimento Sexual/complicações , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina , Hérnia Inguinal/complicações , Humanos , Hormônio Luteinizante/sangue , Masculino , Síndrome , Testosterona/sangue
3.
J Clin Endocrinol Metab ; 46(6): 961-70, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-122442

RESUMO

Four postpubertal 46 XY male patients with an inherited form of bilateral gynecomastia were studied to delineate the nature of the disease. Normal serum FSH and moderately elevated serum LH with concomitantly increased circulating levels of testosterone (T) and estradiol (E2) were found persistently in all cases in blood samples drawn at frequent intervals. LRH pituitary stimulation resulted in an exaggerated LH response and a normal FSH response. Chronic administration of T-cyclopentylate failed to decrease serum LH levels. The peripheral conversion rate of androstenedione to estrone was within normal limits. All patients had low ejaculate volumes with relatively normal spermatozoa counts. Testicular biopsies revealed normal Leydig cells and complete spermatogenesis. Urological examination disclosed that the prostate gland was extremely small. The breast tissue demonstrated the presence of tubular structures as well as the specific binding of [3H]T and [3H]dihydrotestosterone (DHT), which was inhibited by nonlabeled T, DHT, E2, and progesterone, but not by cortisol. The pedigree suggested a recessive X-linked inherited trait. A patient with a nonfamilial form of gynecomastia served as a control in all studies. These data were interpreted as demonstrating that this inherited type of gynecomastia represents the mildest expression of the androgen resistance syndromes and, therefore, belongs to the type 1 form of familial incomplete male pseudohermaphroditism.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Ginecomastia/genética , Hormônio Luteinizante/sangue , Testosterona/sangue , Adolescente , Transtornos do Desenvolvimento Sexual/fisiopatologia , Feminino , Hormônio Liberador de Gonadotropina , Ginecomastia/fisiopatologia , Humanos , Cinética , Masculino , Linhagem , Síndrome , Testículo/patologia
4.
J Clin Endocrinol Metab ; 43(5): 1015-9, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-993309

RESUMO

The circulating levels of of radioimmunoassayable LH and FSH in three postmenopausal women were measured in samples drawn at one minute intervals for a period of 150 or 300 min in order to ascertain the existance of short term oscillation on the plasma content of pituitary gonadotropins. Radioimmunoassay methods and sampling procedures fulfilled all the requirements of quality control. Rapid and non-coincident oscillation in the plasma levels of both LH and FSH at the interval studied were observed in all cases. Statistical analysis disclosed that in addition to short-term gonadotropin fluctuation, the data successfully fit in a 120 min periodic function and the graph resembled a sine wave that was also compatible with an ultradian oscillatory pattern.


Assuntos
Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Menopausa , Feminino , Humanos , Fatores de Tempo
5.
J Clin Endocrinol Metab ; 41(5): 833-40, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1184720

RESUMO

Gonadal function was studied in three post-pubertal siblings (two male and one female) and one unrelated male patient with myotonic dystrophy. The diagnosis was confirmed in all cases by electromyography and muscle biopsy. Basal levels of plasma immunoreactive LH, FSH, testosterone, and estradiol were measured. Hypothalamic, pituitary, and gonadal reserve and responsiveness were evaluated by clomiphene, LHRH, and HCG tests. Histologic examination of gonadal biopsies was also performed. The results showed that gonadal failure present in the four patients had different characteristics. In the same family, hypothalamic amenorrhea was observed in the female patient, and hypothalamic eunuchoidism and hypergonadotropic hypogonadism with marked tubular and leydig cells failure in the male patients. The non-related male patient had hypergonadotropic hypogonadism with tubular failure but with a compensatory leydig-cell hyperplasia. These data are interpreted as demonstrating different expressivity of the hypogonadism associated with the same inherited muscle disease.


Assuntos
Hipogonadismo/fisiopatologia , Hipotálamo/fisiopatologia , Distrofia Miotônica/fisiopatologia , Hipófise/fisiopatologia , Testículo/fisiopatologia , Adulto , Clomifeno/farmacologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Genes Dominantes , Humanos , Hipogonadismo/sangue , Hipogonadismo/genética , Hormônio Luteinizante/sangue , Masculino , Distrofia Miotônica/sangue , Distrofia Miotônica/genética , Linhagem , Progesterona/farmacologia , Testículo/patologia , Testosterona/sangue
6.
J Clin Endocrinol Metab ; 41(5): 946-52, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1184725

RESUMO

A 16-yr-old 46 XY individual with a familial incomplete male pseudohermaphroditism closely resembling the syndrome described by Gilbert-Dreyfus et al. was studied. The patient's habitus was masculine despite the presence of a small phallus, pseudo-vaginal perineal hypospadias, bifid scrotum, gynecomastia, and diminished virilization. Blood samples obtained at 20-min intervals were submitted to hormone analysis. Episodic fluctuations of plasma gonadotropins with mean values of LH above the normal male range and FSH within normal limits were observed. Moderately elevated plasma testosterone and increased plasma estradiol also showed episodic oscillations. The administration of LH-releasing hormone resulted in a significative increase of plasma LH and FSH. Testicular biopsy revealed the presence of seminiferous tubules with few spermatogonia and no spermatocytes, and normal sertoli and interstitial cells. Gonadal stimulation with hCG for 4 consecutive days induced a significative increase of plasma testosterone and estradiol. The daily administration of 50 mg of testosterone propionate for 3 days neither depressed the circulating levels of gonadotropins nor modified the pulsatile pattern of gonadotropins release. Administration of testosterone and 5alpha-dihydrotestosterone propionate failed to diminish plasma LH and FSH levels. Testosterone administration for 10 weeks also failed to induce virilization. These results are similar to those observed in patients with testicular feminization syndrome, and the underlying abnormality involves a partial defect of the mechanism of action of testosterone rather than decreased androgen biosynthesis. According to a recently proposed classification this individual corresponds to the type 1 incomplete male pseudohermaphroditism.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Testosterona/farmacologia , Adolescente , Transtornos do Desenvolvimento Sexual/embriologia , Transtornos do Desenvolvimento Sexual/metabolismo , Humanos , Hipospadia/genética , Masculino , Síndrome , Testículo/embriologia , Testículo/patologia , Testosterona/biossíntese
7.
J Clin Endocrinol Metab ; 52(6): 1257-9, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6785300

RESUMO

Ovulation was induced in a 16-yr-old 46 XX/47 XXY true hermaphrodite with a male phenotype. The presence of testicular tissue was assessed by a normal androgen response to hCG. Administration of FSH and LH for 8 consecutive days, followed by a single dose of hCG, induced a biphasic serum profile of 17 beta-estradiol and progesterone similar to that observed in normal menstrual cycles. In addition, a significant rise in serum testosterone was noticed during the luteal phase. Laparotomy revealed the presence of a uterus, with evidence of endometrial bleeding and absence of a vagina. These results demonstrated that gonadotropins were able to induce follicular maturation, ovulation, and endometrial bleeding in a true hermaphrodite resembling a normal ovulatory cycle. Gonadotropin administration can be used as a diagnostic tool for establishing the presence of ovarian tissue in this gonadal development abnormality.


Assuntos
Transtornos do Desenvolvimento Sexual/fisiopatologia , Indução da Ovulação , Adolescente , Gonadotropina Coriônica , Di-Hidrotestosterona/sangue , Transtornos do Desenvolvimento Sexual/genética , Estradiol/sangue , Hormônio Foliculoestimulante , Humanos , Cariotipagem , Hormônio Luteinizante , Masculino , Fenótipo , Progesterona/sangue , Testosterona/sangue
8.
J Clin Endocrinol Metab ; 61(5): 926-32, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4044781

RESUMO

The present study was conducted to investigate whether the early (2-8 h) testicular response to a single dose of exogenous hCG depends on previous exposure to LH activity. Four different groups of subjects were studied: 1) four normal adult men [Tanner stage-G5 (T-G5)] and one late pubertal subject (T-G4); 2) normal prepubertal (T-G1) and early- and midpubertal boys (T-G2 and T-G3) (n = 4-6 each); 3) five patients with hypogonadotropic hypogonadism (HH); and 4) two patients with the complete form of the androgen insensitivity syndrome. Each subject received an im injection of hCG (40 IU/kg) on day 1 and blood samples were drawn before and 1-8, 24, 48, and 72 h after injection. At 96 h, a second dose of hCG was given (80 IU/kg) and blood samples were obtained at the same times as after the first hCG dose. Serum testosterone (T) was measured by RIA. The first dose of hCG evoked a biphasic response of serum T in groups T-G2 to T-G5 as well as in the two patients with the complete form of the androgen insensitivity syndrome. The early peak was at 2-7 h, whereas the late T peak was at 48-72 h after injection. In T-G1 children and in patients with HH, the early response did not occur [T-G1, from 129 +/- 43 (SEM) to 288 +/- 127 pg/ml (P greater than 0.05); HH, 79 +/- 18 to 107 +/- 12 (P greater than 0.05) pg/ml], and the late peak was attenuated as compared with the pubertal boys. There were not significant differences in the responses of the T-G1 and the HH groups. After the second dose, all groups had biphasic T responses, although they varied in magnitude. These results demonstrate that previous exposure to LH activity is an obligatory prerequisite for the early peak of the hCG-mediated biphasic testicular response, and that a single dose of hCG has a priming effect that is sufficient to ensure a biphasic response to a second dose of hCG given 96 h later.


Assuntos
Gonadotropina Coriônica/farmacologia , Hormônio Luteinizante/farmacologia , Testículo/metabolismo , Testosterona/sangue , Adolescente , Adulto , Androgênios/fisiologia , Criança , Gonadotropina Coriônica/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Masculino , Síndrome , Fatores de Tempo
9.
J Clin Endocrinol Metab ; 63(2): 360-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3088022

RESUMO

The clinical and endocrine features of a unique form of adrenal insufficiency secondary to an inherited deficiency of 3 beta-hydroxysteroid dehydrogenase-isomerase (3-HSD) were studied. The propositus was a 19-yr-old man with a history of repeated episodes of acute adrenal crisis. Family study disclosed that a 6-yr-old female sibling also was affected, and a third sibling had died during the course of an adrenal crisis. The diagnosis of adrenal insufficiency was established on the basis of extremely low serum cortisol levels and urinary 17-hydroxycorticosteroid excretion with concomitantly elevated serum ACTH levels and lack of cortisol response to ACTH administration. Impairment of C-21 steroid 3-HSD activity was strongly suggested by persistency elevated serum 17-hydroxypregnenolone to 17-hydroxyprogesterone and pregnenolone to progesterone ratios, their significant increase after ACTH administration, and their return to normal during cortisol therapy in both patients. Nevertheless, the serum dehydroepiandrosterone to androstenedione ratio, both basally and after ACTH and/or hCG stimulation, was normal. These findings coupled with the normal phenotypic development and onset of puberty in the two patients indicated intact C-19 steroid 3-HSD activity. The overall results indicate an inherited impairment of 3-HSD activity confined only to C-21 steroid substrates and, thus, suggest the existence of at least two 3-HSD isoenzymes under independent genetic regulation.


Assuntos
3-Hidroxiesteroide Desidrogenases/deficiência , Hiperplasia Suprarrenal Congênita/genética , Isoenzimas/sangue , Isomerases/deficiência , Complexos Multienzimáticos/deficiência , Progesterona Redutase/deficiência , Esteroide Isomerases/deficiência , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/enzimologia , Adulto , Criança , Feminino , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Humanos , Isoenzimas/genética , Hormônio Luteinizante/sangue , Masculino , Complexos Multienzimáticos/sangue , Complexos Multienzimáticos/genética , Linhagem , Fenótipo , Progesterona Redutase/sangue , Progesterona Redutase/genética , Esteroide Isomerases/sangue , Esteroide Isomerases/genética
10.
J Clin Endocrinol Metab ; 60(4): 639-43, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2857728

RESUMO

A 46,XY phenotypically male patient with 17-ketosteroid reductase deficiency is described. The patient was a 6-month-old infant who presented with micropenis and bilateral cryptorchidism. Baseline plasma levels of testosterone (T), delta 4-androstenedione (delta 4A), and 5 alpha-dihydrotestosterone (5 alpha-DHT) were within the normal range [patient: 0.17 (T), 0.12 (delta 4A), and 0.032 (5 alpha-DHT) ng/ml; normal infants: 0.03-0.55 (T), 0.14-0.45 (delta 4A), and 0.01-0.23 (5 alpha-DHT) ng/ml]. hCG administration induced a significant rise in plasma delta 4A levels (up to 8.39 ng/ml) and a slight increase in T and 5 alpha-DHT levels. The delta 4A/T ratios before and during the hCG challenge were 0.86 and 55.61, respectively (controls: 0.83 and 0.13). Incubation of genital skin-derived fibroblasts from the patient with either [3H]T or [3H] delta 4A revealed normal formation of delta 4A from T and diminished conversion of delta 4A to T. The development of a male phenotype despite both a testicular and peripheral 17-ketosteroid reductase deficiency is difficult to explain. It is possible that the fetal testes were the source of sufficient amounts of T during the early periods of embryonic life, and that late onset of the enzyme deficiency prevented the development of completely normal male genitalia. The in vitro finding of normal T to delta 4A conversion by the mutant fibroblasts suggests that in this particular tissue 17 beta-reduction and dehydrogenation of androgens are mediated by two isoenzymes with distinct substrate and/or cofactor specificities.


Assuntos
17-Hidroxiesteroide Desidrogenases/deficiência , Criptorquidismo/enzimologia , Pênis/anormalidades , Adolescente , Adulto , Androstenodiona/biossíntese , Células Cultivadas , Criança , Pré-Escolar , Gonadotropina Coriônica , Criptorquidismo/metabolismo , Di-Hidrotestosterona/biossíntese , Fibroblastos/metabolismo , Hormônio Foliculoestimulante/sangue , Humanos , Lactente , Hormônio Luteinizante/sangue , Masculino , Fenótipo , Testosterona/sangue , Testosterona/metabolismo
11.
J Clin Endocrinol Metab ; 53(2): 254-7, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6788790

RESUMO

Hypothalamic-pituitary gonadotropin function was evaluated in two postpubertal XX males. Serum levels of LH and FSH were moderately elevated, and the serum testosterone level was low. A subnormal response by testicular Leydig cells to hCG was observed. The LH and FSH responses to LRH were normal. A significant LH increase was observed after castration. Weekly administration of testosterone enanthate (250 mg) for 10 consecutive weeks caused a reduction (greater than 75%) in gonadotropins and abolishment of the LRH pituitary response. No differences were observed in terms of gonadotropin dynamics compared with other forms of hypergonadotropic hypogonadism. These results indicate that XX males exhibit hypergonadotropic hypogonadism secondary to testicular failure with a preserved androgen responsiveness of the hypothalamic-pituitary unit.


Assuntos
Hormônio Foliculoestimulante/sangue , Hipogonadismo/sangue , Hormônio Luteinizante/sangue , Aberrações dos Cromossomos Sexuais/sangue , Adulto , Castração , Hormônio Liberador de Gonadotropina , Humanos , Hipogonadismo/etiologia , Masculino , Pessoa de Meia-Idade , Aberrações dos Cromossomos Sexuais/complicações , Aberrações dos Cromossomos Sexuais/tratamento farmacológico , Testículo/fisiologia , Testosterona/análogos & derivados , Testosterona/uso terapêutico
12.
J Clin Endocrinol Metab ; 61(4): 790-3, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4031019

RESUMO

Administration of opiate receptor antagonists augmented pulsatile LH release in six estrogen-treated, orchidectomized individuals with testicular feminization. In response to an opiate antagonist, LH pulse frequency increased from 3.0 +/- 0.55 (+/- SE) to 5.0 +/- 0.45 pulses/8 h (P = 0.034). Since these patients have inborn target tissue resistance to androgens, we infer that sustained androgen action is not obligatory to the emergence of endogenous inhibitory opiate tone in man. Rather, these observations document that the suppressive effects of opiates on gonadotropin secretion can be unmasked in the presence of an unopposed estrogen milieu.


Assuntos
Síndrome de Resistência a Andrógenos/sangue , Endorfinas/fisiologia , Estrogênios/fisiologia , Hormônio Luteinizante/metabolismo , Adolescente , Adulto , Síndrome de Resistência a Andrógenos/terapia , Castração , Estradiol/administração & dosagem , Feminino , Humanos , Naloxona , Naltrexona
13.
J Endocrinol ; 121(1): 149-56, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2715754

RESUMO

To investigate the participation of intracellular steroid hormone receptors in the sexual transformation process of the Harderian gland, a series of experiments were undertaken in adult golden hamsters. The invitro labelling of cytosolic steroid-binding sites with appropriate radioligands revealed the presence of androgen, oestrogen and glucocorticoid but not progestin receptors in the glands from animals of both sexes. The androgen receptor of the female gland was further characterized because it was found to be the predominant intracellular steroid receptor. Studies of binding kinetics using [3H]7 alpha,17 alpha-dimethyl-17 beta-hydroxy-4-oestren-3-one (DMNT) as ligand, demonstrated a high affinity androgen-binding site with an apparent dissociation constant (Kd) of 0.7 nmol/l and maximal saturation binding capacity of 84.0 +/- 3.0 (S.D.) fmol/mg protein. Specificity of the androgen receptor was assessed by displacement analysis; DMNT, 5 alpha-dihydrotestosterone, testosterone and 3 alpha-androstanediol were efficient competitors for the androgen-binding site, while oestradiol-17 beta, progesterone and dexamethasone exhibited very little, if any, competitive potency. The sedimentation coefficient of the androgen receptor in sucrose density gradients was 8-9 S. These data indicate that the physicochemical characteristics of the androgen receptor from the female gland are similar to those previously described in the male gland. The striking observation of a complete lack of oestrogen-inducible and oestrogen-insensitive progestin receptors in glands cytosol, even after stimulation with cholera toxin, adds further support to the concept that the androgen receptor is the key molecule mediating the hormone-induced sexual transformation of the Harderian gland in this species.


Assuntos
Cricetinae/metabolismo , Glândula de Harder/análise , Aparelho Lacrimal/análise , Mesocricetus/metabolismo , Receptores de Esteroides/análise , Caracteres Sexuais , Animais , Feminino , Glândula de Harder/crescimento & desenvolvimento , Masculino , Receptores Androgênicos/análise , Receptores de Estrogênio/análise , Receptores de Glucocorticoides/análise , Receptores de Progesterona/análise
14.
J Endocrinol ; 112(1): 3-8, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3819631

RESUMO

Studies were conducted in castrated golden hamsters to assess whether sexual dimorphism and sensitivity to sex steroid hormones in the rodent Harderian gland are mediated by an interaction of androgens with specific intracellular receptors. Physical properties, binding kinetics and stereospecificity of the androgen receptor were analysed using [3H]mibolerone as the radioligand. The presence of [3H]mibolerone-androgen receptor complexes with a sedimentation coefficient of 7-8S was demonstrated in Harderian gland cytosol by a linear sucrose gradient ultracentrifugation technique using a vertical rotor. Kinetic analysis revealed an androgen-binding site with an apparent dissociation constant of 0.3 +/- 0.07 (S.D.) nmol/l and a saturation binding capacity of 113 +/- 15 fmol/mg protein. Displacement studies indicated that unlabelled mibolerone, methyltrienolone, 5 alpha-dihydrotestosterone and testosterone were efficient competitors for the androgen-binding sites, while progesterone, 17 beta-oestradiol, dexamethasone, dehydroepiandrosterone, ethiocholanolone and 5 alpha-16-androsten-3-one were not. Experiments in longterm castrated animals revealed that the Harderian gland androgen receptor concentration and sedimentation coefficient remained unmodified. The results of these studies were interpreted as demonstrating the presence of a specific high-affinity intracellular androgen receptor in the male hamster Harderian gland.


Assuntos
Cricetinae/metabolismo , Glândula de Harder/metabolismo , Aparelho Lacrimal/metabolismo , Mesocricetus/metabolismo , Receptores Androgênicos/metabolismo , Animais , Centrifugação com Gradiente de Concentração , Citosol/metabolismo , Masculino , Orquiectomia , Receptores Androgênicos/análise
15.
J Endocrinol ; 142(2): 311-6, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7931003

RESUMO

We have determined the presence and distribution of intracellular progesterone receptors (PRs) and glucocorticoid receptors (GRs) in the lung of adult female rabbits using immunohistochemistry. The effects of ovariectomy and administration of oestradiol benzoate (10 micrograms for 3 consecutive days) upon PR and GR immunoreactivity were also studied. The results demonstrated the presence of both steroid hormone receptors in the female rabbit lung. PR and GR immunoreactivity was predominantly nuclear and located in alveolar epithelial cells and various interstitial cells such as polymorphonuclear leucocytes. Tissue distribution of both receptors was similar in all cases. Oestradiol treatment induced a marked increase in the number of PR immunoreactive cells compared with intact and ovariectomized female animals. Neither ovariectomy nor oestradiol treatment modified the number of GR immunoreactive cells. The presence and localization of intracellular PRs and GRs in several lung cell types suggest that they may play an important role in mediating the effects of progesterone and glucocorticoids in various physiological processes in the rabbit lung. The data also indicated an oestrogen regulation of PRs in the rabbit lung.


Assuntos
Pulmão/química , Receptores de Glucocorticoides/análise , Receptores de Progesterona/análise , Animais , Estradiol/farmacologia , Feminino , Imuno-Histoquímica , Ovariectomia , Coelhos , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos
16.
J Endocrinol ; 165(3): 693-702, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10828854

RESUMO

Gestodene (17 alpha-ethynyl-13 beta-ethyl-17 beta-hydroxy-4, 15-gonadien-3-one) is the most potent synthetic progestin currently available and it is widely used as a fertility regulating agent in a number of contraceptive formulations because of its high effectiveness, safety and acceptability. The observation that contraceptive synthetic progestins exert hormone-like effects other than their progestational activities, prompted us to investigate whether gestodene (GSD) administration may induce oestrogenic effects, even though the GSD molecule does not interact with intracellular oestrogen receptors (ER). To assess whether GSD may exert oestrogenic effects through some of its neutral metabolites, a series of experimental studies were undertaken using GSD and three of its A-ring reduced metabolites. Receptor binding studies by displacement analysis confirmed that indeed GSD does not bind to the ER, whereas its 3 beta,5 alpha-tetrahydro reduced derivative (3 beta GSD) interacts with a relative high affinity with the ER. The 3 alpha,5 alpha GSD isomer (3 alpha GSD) also binds to the ER, though to a lesser extent. The ability of the A-ring reduced GSD derivatives to induce oestrogenic actions was evaluated by the use of two different molecular bioassays: (a) transactivation of a yeast system co-transfected with the human ER alpha (hER alpha) gene and oestrogen responsive elements fused to the beta-galactosidase reporter vector and (b) transactivation of the hER alpha-mediated transcription of the chloramphenicol acetyl transferase (CAT) reporter gene in a HeLa cells expression system. The oestrogenic potency of 3 beta GSD was also assessed by its capability to induce oestrogen-dependent progestin receptors (PR) in the anterior pituitary of castrated female rats. The results demonstrated that 3 beta GSD and 3 alpha GSD were able to activate, in a dose-dependent manner, the hER alpha-mediated transcription of both the beta-galactosidase and the CAT reporter genes in the yeast and HeLa cells expression systems respectively. In both assays the 3 beta derivative of GSD exhibited a significantly greater oestrogenic effect than its 3 alpha isomer, while unchanged GSD and 5 alpha GSD were completely ineffective. Neither 3 beta GSD nor 3 alpha GSD exhibited oestrogen synergistic actions. Interestingly, the pure steroidal anti-oestrogen ICI-182,780 diminished the transactivation induced by 3 beta GSD and 3 alpha GSD in the yeast expression system. Furthermore, administration of 3 beta GSD resulted in a significant increase of oestrogen-dependent PR in the anterior pituitaries of castrated rats in comparison with vehicle-treated animals. The characteristics of the 3 beta GSD-induced PR were identical to those induced by oestradio benzoate. The overall results demonstrate that 3 beta GSD and its 3 alpha isomeric alcohol specifically bind to the ER and possess a weak intrinsic oestrogenic activity, whereas unmodified GSD does not. The data contribute to a better understanding of the GSD mechanism of action and allow the hypothesis to be advanced that the slight oestrogenlike effects attributable to GSD are mediated by its non-phenolic, tetrahydro reduced metabolites.


Assuntos
Anticoncepcionais Orais Sintéticos/farmacologia , Norpregnenos/farmacologia , Congêneres da Progesterona/farmacologia , Animais , Ligação Competitiva , Anticoncepcionais Orais Sintéticos/metabolismo , Feminino , Células HeLa , Humanos , Norpregnenos/metabolismo , Oxirredução , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Congêneres da Progesterona/metabolismo , Ratos , Ratos Wistar , Receptores de Estradiol/metabolismo , Receptores de Progesterona/biossíntese , Saccharomyces cerevisiae/genética , Ativação Transcricional/efeitos dos fármacos
17.
Am J Med Genet ; 55(3): 356-8, 1995 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-7726236

RESUMO

Most individuals with the rare 46,XX male "syndrome" arise due to an unequal interchange between Xp and Yp termini during paternal meiosis. The pattern of Y-sequences in these patients varies considerably, but very few cases have been reported showing only SRY. The phenotype in these patients is also variable ranging from severe impairment of the external genitalia through hypospadias and/or cryptorchidism to occasional normal male phenotype. We report a Mexican 46,XX male patient without genital ambiguities in whom DNA analysis showed the presence of SRY and the absence of ZFY. We conclude that in this case SRY alone was enough for complete male sexual differentiation.


Assuntos
Proteínas de Ligação a DNA/genética , Transtornos do Desenvolvimento Sexual/genética , Proteínas Nucleares , Aberrações dos Cromossomos Sexuais/genética , Diferenciação Sexual/genética , Fatores de Transcrição , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/fisiologia , Nanismo/genética , Feminino , Humanos , Fatores de Transcrição Kruppel-Like , Masculino , Oligospermia/genética , Proteína da Região Y Determinante do Sexo , Sindactilia/genética , Testículo/anormalidades
18.
Am J Med Genet ; 46(3): 263-7, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8488868

RESUMO

We describe clinical, cytogenetic, endocrine, and histopathological findings in 16 patients with mixed gonadal dysgenesis (MGD). All patients except 1 presented genital ambiguity and 10 of them had Ullrich-Turner manifestations. The 45,X/46,XY karyotype was the most frequent with a predominance of 45,X cells in both peripheral lymphocytes and gonads. In all cases Müllerian and Wolffian remnants and/or derivatives were found and in some patients both Wolffian- and Müllerian-derived structures were identified on the streak or testicular side. Postpubertal patients exhibited variable degrees of virilization and all of them had hypergonadotropism coexisting with low to normal baseline serum levels of testosterone; their testicular response to human chorionic gonadotropin (HCG) in terms of testosterone secretion was also variable, ranging from minimal to almost a normal response. All prepubertal patients but 1 had normal baseline levels of pituitary gonadotropins and testosterone and their gonadal response to the HCG challenge was highly variable. With the exception of 1 case, who had a 45,X/46,XY(p-) karyotype, no correlation between the cytogenetic data and degree of external genital ambiguity and the hormonal findings was observed. Additional information on the specific structural abnormalities involving the testis-determining gene of the Y chromosome in patients with MGD is needed in order to further understand the mechanisms responsible for the wide variability characteristic of this disorder.


Assuntos
Disgenesia Gonadal Mista/patologia , Adulto , Criança , Pré-Escolar , Disgenesia Gonadal Mista/genética , Disgenesia Gonadal Mista/fisiopatologia , Humanos , Lactente , Cariotipagem , Masculino , Mosaicismo , Ductos Paramesonéfricos , Testosterona/metabolismo
19.
Am J Med Genet ; 63(2): 348-55, 1996 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-8725784

RESUMO

True hermaphroditism is characterized by the development of ovarian and testicular tissue in the same individual. Müllerian and Wolffian structures are usually present, and external genitalia are often ambiguous. The most frequent karyotype in these patients is 46,XX or various forms of mosaicism, whereas 46,XX is very rarely found. The phenotype in all these subjects is similar. We studied 10 true hermaphrodites. Six of them had a 46,XX chromosomal complement: 3 had been reared as males and 3 as females. The other 4 patients were mosaics: 3 were 46,XX/46,XY and one had a 46,XX/47,XXY karyotype. One of the 46,XX/46,XY mosaics was reared as a female, whereas the other 3 mosaics were reared as males. The sex of assignment in the 10 patients depended only on labio-scrotal differentiation. Molecular studies in 46,XX subjects documented the absence of Y centromeric sequences in all cases, arguing against hidden mosaicism. One patient presented Yp sequences (ZFY+, SRY+), which contrast with South African black 46,XX true hermaphrodites in whom no Y sequences were found. Molecular analysis in the subjects with mosaicism demonstrated the presence of Y centromeric and Yp sequences confirming the presence of a Y chromosome. Gonadal development, endocrine function, and phenotype in the 10 patients did not correlate with the presence of a Y chromosome or Y-derived sequences in the genome, confirming that true hermaphroditism is a heterogeneous condition.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Proteínas Nucleares , Fatores de Transcrição , Cromossomo Y , Adolescente , Adulto , Criança , Pré-Escolar , Proteínas de Ligação a DNA/genética , Feminino , Disgenesia Gonadal 46 XY , Humanos , Lactente , Cariotipagem , Fatores de Transcrição Kruppel-Like , Masculino , Fenótipo , Análise para Determinação do Sexo , Proteína da Região Y Determinante do Sexo
20.
Eur J Endocrinol ; 132(4): 502-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7711890

RESUMO

The reproductive hormonal profile was evaluated in female rats with experimental nephrotic syndrome induced with a single subcutaneous dose of puromycin aminonucleoside (PAN). Serum concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4), testosterone and 17 beta-estradiol (E2) were determined sequentially in control and experimental groups on days 1, 3, 7 and 10 after PAN administration. Prolactin levels were also assessed on day 10. In both groups, vaginal smears were taken daily throughout the study to evaluate cyclic histological changes. At the end of the experiment the histological appearance of the ovaries was evaluated by light microscopy. Nephrotic rats had a rapid loss of the estrous cycle starting on day 4, which set them at diestrus. At the same time the hormonal evaluation indicated a gradual decrease in E2, LH and P4 concentrations, starting from days 3, 7 and 10, respectively. No significant changes were noted in FSH or testosterone values. Besides, on day 10, prolactin concentrations remained unmodified. Even though most hormonal levels were found low on day 10, all values except E2 (undetectable) corresponded to the interval reported for the diestrus phase. Likewise, histological examination of ovarian tissue from nephrotic rats showed a considerable increase in the number of atretic follicles. These findings indicate that female rats with nephrotic syndrome develop an important endocrine dysfunction that probably involves steroidogenic tissues (ovary and/or adrenal gland), and suggest the existence of a hypothalamic-hypophyseal impairment.


Assuntos
Síndrome Nefrótica/fisiopatologia , Ovário/fisiopatologia , Hipófise/fisiopatologia , Animais , Estradiol/sangue , Estro/fisiologia , Feminino , Hormônio Foliculoestimulante/sangue , Hipotálamo/fisiologia , Hormônio Luteinizante/sangue , Síndrome Nefrótica/sangue , Síndrome Nefrótica/induzido quimicamente , Progesterona/sangue , Prolactina/sangue , Puromicina Aminonucleosídeo , Ratos , Ratos Wistar , Testosterona/sangue
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