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1.
Science ; 169(3952): 1326-7, 1970 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-4318262

RESUMO

We have analyzed 88 pregnancies in 50 women who had previously been treated for gestational trophoblastic neoplasms with chemotherapeutic agents. No increase in fetal wastage, congenital abnormalities or complicated pregnancies was noted, suggesting that these drugs do not damage human oocytes in the doses and time periods used. The possibility that recessive mutations have been induced but were undetected cannot be evaluated definitively at present.


Assuntos
Antineoplásicos/uso terapêutico , Complicações na Gravidez/tratamento farmacológico , Gravidez , Neoplasias Trofoblásticas/tratamento farmacológico , Aborto Espontâneo , Descolamento Prematuro da Placenta , Compostos Azo/uso terapêutico , DNA/biossíntese , Dactinomicina/uso terapêutico , Surdez/genética , Eczema/congênito , Edema , Feminino , Morte Fetal , Seguimentos , Bócio/genética , Hemangioma/congênito , Humanos , Hiperêmese Gravídica , Iodo/metabolismo , Mecloretamina/uso terapêutico , Metotrexato/uso terapêutico , Mutação , Placenta Acreta , Hemorragia Pós-Parto , Estrabismo/congênito , Tetralogia de Fallot , Vimblastina/uso terapêutico
2.
J Clin Invest ; 46(5): 891-902, 1967 May.
Artigo em Inglês | MEDLINE | ID: mdl-6025489

RESUMO

The average plasma testosterone concentration of women with either hirsutism or polycystic ovaries and hirsutism was higher (p < 0.01) than that of normal women although the ranges overlapped. Testosterone blood production rates averaged 830 +/- 120 SE and 1,180 +/- 310 SE mug per day in the two groups of hirsute women and 230 +/- 33 SE mug per day in normal women. The ranges did not overlap. The testosterone metabolic clearance rates of hirsute women (1,090 +/- 140 SE L per day) and of men (1,240 +/- 136 SE L per day) were significantly higher than those of normal women (590 +/- 44 SE L per day). These differences persisted when the metabolic clearance rates were corrected for surface area. We suggest that testosterone metabolic clearance rates vary directly with some function of testosterone production. The mean plasma androstenedione levels (2.8 +/- 0.35 SE and 2.8 +/- 0.30 SE mug per L) and production rates (6,060 +/- 450 SE and 7,360 +/- 345 SE mug per day) of the women with hirsutism or polycystic ovaries, respectively, were significantly higher than those of normal women (1.5 +/- 0.22 SE mug per L; 3,300 +/- 830 SE mug per day). The androstenedione metabolic clearance rates were the same in each group. Plasma androstenedione was the precursor of 49% of plasma testosterone in normal women and of 26% of plasma testosterone in hirsute women. Thus, 74% of the plasma testosterone in these subjects must have been either secreted or derived from a precursor that did not enter the plasma androstenedione pool.


Assuntos
17-Cetosteroides/metabolismo , Hirsutismo/metabolismo , Síndrome do Ovário Policístico/metabolismo , Testosterona/metabolismo , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade
3.
J Clin Invest ; 48(5): 930-9, 1969 May.
Artigo em Inglês | MEDLINE | ID: mdl-4305376

RESUMO

Plasma 17-hydroxyprogesterone (17-OHP) concentrations in normal men averaged 0.094 mug/100 ml. Studies using suppressive doses of androgens and glucocorticoids showed that 90% of the 17-OHP originated from the Leydig cell. The 17-OHP production rate was 1.8 mg/24 hr. Plasma 17-OHP has a marked circadian variation, the 8 p.m. values being only 40% of the 8 a.m. values. Plasma luteinizing hormone measured in the same samples did not vary. The adrenal cortex has the capacity to synthesize and secrete 17-OHP and progesterone since adrenocorticotrophic hormone (ACTH) caused a fourfold increase in these plasma steroids. In children with congenital adrenal hyperplasia, plasma 17-OHP levels were 50-200 times those of normal men and plasma progesterone was increased 6- to 10-fold over normal men.


Assuntos
Hiperplasia Suprarrenal Congênita , Hiperfunção Adrenocortical/sangue , Hidroxiprogesteronas/sangue , Células Intersticiais do Testículo/metabolismo , Progesterona/sangue , Adolescente , Hormônio Adrenocorticotrópico/farmacologia , Adulto , Criança , Gonadotropina Coriônica/farmacologia , Ritmo Circadiano , Dexametasona/farmacologia , Feminino , Fluoximesterona/farmacologia , Humanos , Hidroxiprogesteronas/biossíntese , Hiperplasia/sangue , Hiperplasia/congênito , Hormônio Luteinizante/sangue , Masculino , Menstruação , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
4.
J Clin Invest ; 48(10): 1809-19, 1969 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-5822587

RESUMO

We have attempted to measure the metabolic clearance rates (MCR) and the transfer factors of estradiol (E(2)) and estrone (E(1)) during 2-hr and 12-hr infusions. When estradiol-(3)H was infused for 2 hr, apparent equilibrium was reached at 70 min; the 12-hr infusions showed that plasma estradiol-(3)H levels increased slowly throughout the infusion. When estrone-(3)H was infused, constancy of estrone-(3)H levels was not attained in either the 2-hr infusions or in the two 12-hr infusions. The tritium level in the metabolite of the infused estrogen did not become constant in 50% of the short infusions and increased during all the long infusions. Thus, the conversion ratios C(E1E2) and C(E2E1) continually changed and transfer factors could not be calculated. The apparent "MCR'S" calculated on the basis of the 2-hr studies expressed as liters/24 hr per m(2) +/-SD were: "MCR(E1)" (women) 980 +/-94, (men) 1170 +/-95; "MCR(E2)" (women) 615 +/-17, (men) 830 +/-30. The estradiol "MCR's" differed significantly between men and women. "MCR(E2)" was the same using either estradiol-(14)C or -(3)H and was unchanged by the infusion of 170 mug of estradiol daily. Postmenopausal women had estrogen "MCR's" in the same range as premenopausal women. Excess glucocorticoids increased the "MCR(E2)."


Assuntos
Estrogênios/metabolismo , Taxa de Depuração Metabólica , Adulto , Estradiol/administração & dosagem , Estradiol/metabolismo , Estrona/administração & dosagem , Estrona/metabolismo , Feminino , Glucocorticoides , Humanos , Cinética , Masculino , Menopausa , Trítio
5.
J Clin Invest ; 49(11): 1999-2007, 1970 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4248912

RESUMO

A reliable radio-ligand assay has been developed for the measurement of 17-hydroxypregnenolone in human peripheral vein plasma. The mean plasma concentration of 17-hydroxypregnenolone was, in men, 1.9 mmug/ml; and in women, 3.5 mmug/ml. These means were not significantly different from each other, and the levels were the same in the follicular and luteal phases of the menstrual cycle. In women, the adrenal cortex was the source of the 17-hydroxypregnenolone; in men, 40% was produced by the testis. Since the metabolic clearance rate was about 2000 liters/24 hr production rate estimates were 4-7 mg/24 hr. The conversion of blood 17-hydroxypregnenolone to blood 17-hydroxyprogesterone and dehydroepiandrosterone was measured. This varied from 5 to 20%. Thus, in women during the follicular phase, 17-hydroxyprogesterone derived from blood 17-hydroxypregnenolone could be the major fraction of the 17-hydroxyprogesterone production rate. Blood 17-hydroxypregnenolone is a minor precursor of blood dehydroepiandrosterone.


Assuntos
Glândulas Suprarrenais/metabolismo , Hidroxiprogesteronas/metabolismo , Pregnanos/biossíntese , Pregnanos/sangue , Testículo/metabolismo , 17-alfa-Hidroxipregnenolona/sangue , 17-alfa-Hidroxipregnenolona/metabolismo , Cromatografia em Camada Fina , Ritmo Circadiano , Desidroepiandrosterona/metabolismo , Dexametasona , Estradiol/biossíntese , Feminino , Fluoximesterona , Humanos , Masculino , Menstruação , Taxa de Depuração Metabólica , Métodos , Pregnanos/metabolismo , Ligação Proteica , Fatores Sexuais , Testosterona/biossíntese
6.
J Clin Invest ; 50(6): 1338-44, 1971 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-5103749

RESUMO

Dihydrotestosterone metabolism was studied with a constant infusion technique in three men, three women, five hirsute women, and four estrogen-treated hirsute women. The mean dihydrotestosterone metabolic clearance rate was higher in men (336 liters/24 hr per m(2) [range, 239-448]) than in women (153 liters/24 hr per m(2) [range, 108-184]). The metabolic clearance rates in hirsute patients were intermediate between those men and women and were decreased by estrogen treatment. These observations demonstrate similarities in the metabolic rates of testosterone and dihydrotestosterone. The conversion of plasma testosterone and androstenedione to dihydrotestosterone was studied in men and hirsute women. Approximately 4 and 2% of plasma testosterone and androstenedione, respectively, were converted to plasma dihydrotestosterone in both groups. From these observations it was determined that a major fraction of plasma dihydrotestosterone was derived from these plasma precursors rather than from glandular secretion. Both 5alpha-androstan-3alpha,17beta-diol (3alpha-diol) and 5alpha-androstan-3beta,17beta-diol (3beta-diol) were identified in plasma during dihydrotestosterone and testosterone infusions. The conversion ratio of dihydrotestosterone to 3alpha-diol (C(BB) (DHT-3alpha)) was greater than the conversion ratio to the 3beta-isomer (C(BB) (DTH-3beta)) in all the patients studied. Both C(BB) (DHT-3alpha) and C(BB) (DHT-3beta) were higher in men (mean values of 0.151 [range, 0.110-0.222] and 0..031 [range, 0.022-0.042]) than in women (means of 0.044 [range, 0.037-0.048] and 0.012 [range 0.010-0.013]). A smaller fraction of testosterone was converted to 3alpha-diol and 3beta-diol.


Assuntos
Androstanos/sangue , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/metabolismo , Testosterona/metabolismo , Hiperfunção Adrenocortical/cirurgia , Adulto , Isótopos de Carbono , Coriocarcinoma/metabolismo , Cromatografia em Papel , Cromatografia em Camada Fina , Etinilestradiol/uso terapêutico , Feminino , Fludrocortisona/uso terapêutico , Hirsutismo/metabolismo , Humanos , Hidrocortisona/uso terapêutico , Medroxiprogesterona/uso terapêutico , Taxa de Depuração Metabólica , Cistos Ovarianos/metabolismo , Gravidez , Esteróis/sangue , Trítio
7.
J Clin Invest ; 51(4): 1020-33, 1972 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-5014608

RESUMO

Since estrone sulfate (E(1)S) is present at high concentration in plasma, we have examined the parameters of the plasma estrone, estradiol, E(1)S system. The metabolic clearance rate of E(1)S was 157 liter/day (range 70-292) in men and women. Estimated plasma production rates of E(1)S were (mugrams per day): men, 77; women, early follicular phase, 95; women, early luteal phase, 182. The conversion of plasma estrone and estradiol to E(1)S was measured and from these data and the metabolic clearance rates of the estrogens, the transfer factors were rho(E) (1) (E) (1) (S) = 0.54 and rho(E) (2) (E) (1) (S) = 0.65. Using average production rates, all plasma E(1)S could be shown to be derived from plasma estrone and estradiol. The conversion of plasma E(1)S to plasma estrone and estradiol was studied. The calculated transfer factors were: rho(E) (1) (SE) (1) = 0.21, rho(E) (1) (SE) (2) = 0.014. Essentially, similar data were obtained when E(1)S was given by mouth to two subjects. WE CONCLUDE: (a) E(1)S is a major circulating plasma estrogen and has a long plasma half-life; (b) the large contributions of estrone and estradiol to plasma E(1)S are more than sufficient to account for all the circulating plasma E(1)S.


Assuntos
Estrona/metabolismo , Adolescente , Adulto , Isótopos de Carbono , Cromatografia em Camada Fina , Estradiol/metabolismo , Estrona/sangue , Feminino , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica , Sulfatos/sangue , Sulfatos/metabolismo , Trítio
8.
J Clin Invest ; 48(11): 2046-56, 1969 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4390462

RESUMO

Pituitary and gonadal function was studied in seven chromatin-negative men, ages 15-27 yr, with retarded sexual and somatic development, skeletal anomalies, and hyposmia. These hyposmic patients were compared with normal men, prepuberal boys and hypogonadal patients with hypopituitarism. The urinary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels of hyposmic subjects were the same as those of normal boys and hypopituitary patients but significantly lower than those of normal men. Clomiphene citrate did not cause an increase in plasma FSH and LH levels in either hypogonadal group as it does in normal men. In contrast to hypopituitary patients, thyroid and adrenocortical function and release of growth hormone in the hyposmic subjects were normal. The plasma testosterone levels were equally low in prepuberal, hypopituitary, and hyposmic patients but were increased to a greater extent by human chorionic gonadotropin (HCG) treatment in prepuberal and hypopituitary subjects than in the hyposmic patients. Prolonged treatment with HCG has failed to return plasma testosterone levels to normal in two hyposmic patients. These observations suggest that there are defects of both pituitary and Leydig cell function in men with the syndrome of hypogonadism, skeletal anomalies, and hyposmia. They have impaired secretion of FSH and LH and a Leydig cell insensitivity to gonadotropin.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hipogonadismo/fisiopatologia , Hipopituitarismo/fisiopatologia , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/metabolismo , Transtornos do Olfato/fisiopatologia , Hipófise/metabolismo , Adolescente , Glândulas Suprarrenais/fisiopatologia , Adulto , Arginina , Osso e Ossos/anormalidades , Gonadotropina Coriônica/uso terapêutico , Clomifeno , Criptorquidismo/tratamento farmacológico , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/urina , Hormônio do Crescimento/sangue , Humanos , Hidrocortisona/sangue , Hipogonadismo/complicações , Hipogonadismo/tratamento farmacológico , Sistema Hipotálamo-Hipofisário/fisiopatologia , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Masculino , Metirapona , Transtornos do Olfato/complicações , Osteoporose/fisiopatologia , Testes de Função Hipofisária , Testes de Função Adreno-Hipofisária , Testosterona/sangue , Glândula Tireoide/fisiopatologia
9.
J Clin Invest ; 69(6): 1261-9, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6282933

RESUMO

We have studied a man suspected of having primary cortisol resistance on the basis of high 24-h mean plasma cortisol levels (27.4 micrograms/dl) and no stigmata of Cushing's syndrome. His son had slightly elevated 24-h mean plasma cortisol levels (9.9 micrograms/dl; normal 7.52 micrograms/dl). Both had high plasma protein unbound cortisol and increased urinary free cortisol. Plasma ACTH concentration was high, and both were resistant to adrenal suppression by dexamethasone. The father appeared to have mineralocorticoid excess resulting in hypertension, hypokalemia, and metabolic alkalosis. This was found to be due to markedly elevated plasma levels of deoxycorticosterone and corticosterone. The son, who was normotensive, had mildly increased plasma corticosterone and normal deoxycorticosterone levels. To study the apparent end-organ resistance to cortisol, we examined the glucocorticoid receptor in the white cells and fibroblasts of these patients. In both tissues, using both whole cell and cytosol assays, the glucocorticoid receptor was found to have reduced affinity for dexamethasone. In the cytoxol assays, a reduced receptor number was found as well. We conclude that cortisol resistance is a rare familial syndrome owing to an abnormal glucocorticoid receptor with a decreased affinity for cortisol.


Assuntos
Hiperfunção Adrenocortical/sangue , Hidrocortisona/sangue , Receptores de Glucocorticoides/metabolismo , Receptores de Esteroides/metabolismo , Hiperfunção Adrenocortical/complicações , Hormônio Adrenocorticotrópico/sangue , Adulto , Aldosterona/urina , Alcalose/sangue , Alcalose/complicações , Ritmo Circadiano , Corticosterona/sangue , Desoxicorticosterona/sangue , Dexametasona/sangue , Humanos , Hidrocortisona/urina , Hipopotassemia/sangue , Hipopotassemia/complicações , Masculino , Pessoa de Meia-Idade , Linhagem
10.
J Clin Invest ; 58(5): 1061-8, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-825531

RESUMO

Androgen-binding protein (ABP) has been found in the cytosol of testicular and epididymal homogenates of several sub-primate species. In those species which had the plasma androgen binding protein, testosterone-estradiol-binding globulin (TeBG), ABP and TeBG were found to be physically similar. We investigated the possibility that ABP might exist in monkey and man using the cytosol of testicular and epididymal homogenates and aspirates obtained by direct micropuncture of the rete testis. In polyacrylamide gel electrophoresis, pH 7.8, testicular and epididymal cytosols of monkey and man were found to contain several binding proteins of different size and net charge that bind dihydrotestosterone. These binding proteins were either indistinguishable from TeBG or could be related to TeBG as size and/or charge isomers. No ABP was detectable in up to 200 mul of monkey rete testis fluid obtained by direct micropuncture, though ABP is detectable in as little as 5 mul of rat rete testis fluid. The data suggest that the ABP's detected in the testicular and epididymal cytosols in monkey and man represent isomeric forms of plasma TeBG, and their presence in testicular cytosol most likely derives from blood contamination.


Assuntos
Androgênios , Proteínas de Transporte , Epididimo/análise , Globulina de Ligação a Hormônio Sexual/análise , Testículo/análise , Animais , Di-Hidrotestosterona , Eletroforese em Gel de Poliacrilamida , Haplorrinos , Humanos , Focalização Isoelétrica , Macaca mulatta , Masculino , Globulina de Ligação a Hormônio Sexual/sangue
11.
Cancer Res ; 35(11 Pt. 2): 3359-61, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1104148

RESUMO

The effects of obesity on steroid metabolism in women with breast and uterine cancer have been considered. Obesity may increase plasma estrone by two mechanisms, a higher rate of secretion of the estrone precursor, androstenedione, and a higher rate of conversion of androstenedione to estrone. Obesity may alter routes of metabolism of androgens and estrogens. The excretion of specific urinary metabolites can therefore be altered by obesity alone. Thus, steroid indices of relative cancer risk or responsiveness must be constructed with due attention to obesity, one of many important variables.


Assuntos
Hormônios/metabolismo , Neoplasias/etiologia , Fenômenos Fisiológicos da Nutrição , Androstenodiona/metabolismo , Anovulação/complicações , Neoplasias da Mama/etiologia , Estrogênios/biossíntese , Estrogênios/urina , Estrona/biossíntese , Feminino , Humanos , Obesidade/metabolismo , Neoplasias Uterinas/complicações , Neoplasias Uterinas/metabolismo
12.
Endocrinology ; 108(1): 40-3, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7460827

RESUMO

2-Hydroxyestrone (2-OHE1) has much lower uterotropic potency than might be predicted from its uterine estrogen receptor affinity. 2-OHE1 displaces saturably bound [3H]estradiol from rat uterine cytosol with a competitive inhibition constant of 8.6 nM, while the dissociation constant for 17 beta-estradiol (E2) is 0.42 nM. From this ratio of binding affinities, one would expect some agonist or antagonist activity of 2-OHE1 to be apparent at doses roughly 20-50 times the minimum effective dose of E2. Instead, at doses of 2-OHE1 1000 times an effective dose of E2, no uterotropic effect was observed. When 2-OHE1 was injected together with E2 at dose ratios of 500:1, there was no antagonism of the effect of E2. To examine this discrepancy, the plasma MCRs (MCRpS) of E2 and 2-OHE1 were determined by continuous infusion techniques. Plasma concentrations of 2-OHE1 and E2 during control and infusion periods were measured by RIAs. The MCRp of 2-OHE1 averaged 50,000 ml/h, more than 100 times that of E2 (approximately 400 ml/h). The extraordinarily high MCRp of 2-OHE1 may explain the failure to observe any biological effects of this catechol estrogen, even at high doses. This rapid metabolism, presumably occurring in the blood compartment, should be considered in handling blood samples for RIA and in devising studies of the actions of catechol estrogens.


Assuntos
Estrona/análogos & derivados , Hidroxiestronas/fisiologia , Contração Uterina/efeitos dos fármacos , Animais , Citosol/metabolismo , Feminino , Hidroxiestronas/metabolismo , Hidroxiestronas/farmacologia , Taxa de Depuração Metabólica , Ratos , Útero/metabolismo
13.
Endocrinology ; 96(3): 564-70, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1116475

RESUMO

Hydroxyurea, a chemotherapeutic agent that prevents mitosis by inhibiting DNA synthesis, was administered to adult male rats for 70 days. Plasma FSH and LH showed no systematic trend although severe germinal cell depletion was produced. These data suggest that the cell(s) of the seminiferous tubule involved in FSH regulation must be either the type A spermatogonium or the Sertoli cell.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hidroxiureia/farmacologia , Testículo/citologia , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Mitose , Radioimunoensaio , Ratos , Fatores de Tempo
14.
Endocrinology ; 115(1): 357-61, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6428862

RESUMO

Primates have diverged into three major evolutionary groups: prosimians, Old World primates, and New World primates; the last group is distinguished by high circulating cortisol concentrations and resistance to the action of glucocorticoids. We have studied a large spectrum of primate species within these groups to characterize the phylogenetic relationships of cortisol-binding globulin (CBG) among them. The CBG in each species was found to be glycosylated, as judged from lectin interactions, and to exhibit an electrophoretic mobility similar to that of human CBG. Although the CBG affinity for cortisol differed among species, the effects of changes in temperature on the CBG affinity were similar. Strikingly, the CBG-binding capacity of plasma in the New World primates was 1/10th to 1/100th those in the Old World primates and prosimians, while the CBG-binding affinity for cortisol was lower. The reduced capacity and affinity of CBG result in a markedly higher fraction of unbound plasma cortisol in the New World primates than in the Old World primates or the prosimian species examined. This evolutionary pattern of CBG may be a compensatory mechanism for the target organ resistance to glucocorticoids that characterizes the New World monkeys.


Assuntos
Evolução Biológica , Hidrocortisona/sangue , Primatas/sangue , Transcortina/metabolismo , Animais , Callitrichinae/sangue , Cebidae/sangue , Cromatografia em Gel , Concanavalina A , Eletroforese em Gel de Poliacrilamida , Macaca/sangue , Pan troglodytes/sangue , Papio/sangue , Sefarose , Strepsirhini/sangue
15.
Endocrinology ; 115(1): 25-32, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6329650

RESUMO

Many New World primate species have elevated circulating free plasma cortisol concentrations, target tissue resistance to cortisol, and no evidence of sodium retention. A representative New World primate, the squirrel monkey (Saimiri sciureus), has plasma cortisol concentrations above those necessary to cause complete suppression of the renin-angiotensin-aldosterone axis in an Old World primate, the cynomolgus monkey (Macaca fascicularis). Despite this, the arterial blood pressure as well as the plasma sodium, potassium, and bicarbonate levels of the squirrel monkey are similar to those of the cynomolgus monkey, and its plasma aldosterone concentrations are approximately 2-fold higher. These findings suggest that cortisol has minimal sodium-retaining effects in this species. Renal cytosol aldosterone receptor concentrations are about 2- to 3-fold lower in the squirrel monkey than in the cynomolgus, whereas the receptor affinities for [3H]aldosterone are similar in the two monkeys. Higher concentrations of cortisol are needed to displace [3H]aldosterone from the mineralocorticoid receptor in the squirrel monkey than from the renal receptor in the cynomolgus [apparent equilibrium dissociation constant (Ki) = 7.8 X 10(-7) vs. 2.9 X 10(-8) M, respectively]. In addition, in contrast to man and presumably other Old World primates, plasma aldosterone concentrations in the female squirrel monkey do not increase during the reproductive cycle or pregnancy when progesterone concentrations are 10- to 20-fold higher than those of the male or the reproductively quiescent female. This suggests that progesterone is a poor aldosterone antagonist in this species. We conclude that a low concentration of mineralocorticoid receptors in New World Primates is compensated for by higher aldosterone levels, with a concomitant increase in receptor occupancy. The salt-retaining potency of cortisol is low, presumably because of a decrease in the affinity of the aldosterone receptor for glucocorticoids in New World primates.


Assuntos
Cebidae/metabolismo , Hidrocortisona/sangue , Rim/metabolismo , Progesterona/sangue , Receptores de Esteroides/metabolismo , Saimiri/metabolismo , Corticosteroides/sangue , Aldosterona/metabolismo , Animais , Eletrólitos/sangue , Feminino , Hidrocortisona/farmacologia , Macaca fascicularis/metabolismo , Masculino , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides , Renina/sangue , Transcortina/sangue
16.
J Clin Endocrinol Metab ; 37(1): 63-7, 1973 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4577100

RESUMO

PIP: With the use of prepared iodine-125-monoiodo-LH-RH, the disappearance rates of LH-RH (luteinizing hormone-releasing hormone) in man and in the rat were investigated, as well as the distribution of LH-RH in the rat. After 10 microcuries of iodine-125-LH-RH were injected as an iv bolus into 3 male volunteers, blood samples from the opposite arm were obtained through an indwelling venous catheter at 2, 5, 8, 11, 15, 20, 30, 45, and 60 minutes postinjection and at 6 and 24 hours postinjection. To describe the disappearance curve a 3-term exponential equation was necessary and sufficient. The ranges of the t1/2s for the first, second, and third components were 2-4 minutes, 30-55 minutes, and starting at more than 10 hours. The initial distribution space was 3-4.7 1 or 37-47 ml/kg body weight. Similar procedures in the rat (45) resulted in an equation with 2 exponentials, with the ranges of the t1/2s for the first and second components being 5-10 minutes and 150-600 minutes. In both man and rat the distribution volume approximated estimated plasma volume. Following the injection of iodine-125-LH-RH in the rat, pituitary radioactivity increased, as expected, reaching a maximum tissue/serum ratio of 1.5 at 90 minutes. 2 iodinated oligomers of LH-RH were found to have different disappearance rates and distributions in the rat than did iodine-125-LHrh. the disappearance rate of iodine-125-LH-RH in this study is consistent with values for other small peptide hormones.^ieng


Assuntos
Hormônio Luteinizante , Hormônios Liberadores de Hormônios Hipofisários/metabolismo , Animais , Volume Sanguíneo , Meia-Vida , Humanos , Isótopos de Iodo , Rim/metabolismo , Fígado/metabolismo , Masculino , Hipófise/metabolismo , Hormônios Liberadores de Hormônios Hipofisários/sangue , Ratos
17.
J Clin Endocrinol Metab ; 49(3): 396-8, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-468974

RESUMO

Testosterone (T) was given to normal men with and without the concomitant administration of the aromatase inhibitor, delta 1-testolactone (Teslac), to examine the role of peripheral aromatization of T in gonadotropin regulation. When T was administered alone by continuous iv infusion (15 mg/day for 4 days), serum T increased 3-fold (P less than 0.01) and estradiol (E) increased by 50% (P less than 0.01). These changes were associated with a 50% decrease in serum LH and FSH concentrations (P less than 0.01). When T was infused into men taking Teslac (2000 mg/day), serum T levels doubled (P less than 0.01), but E levels did not change (13.4 +/- 1.5 vs. 13.5 +/- 1.0 pg/ml; P = NS). This pattern of plasma steroids, increased T and unchanged E, was also associated with significantly decreased serum LH and FSH concentrations (14.5 +/- 0.4 vs. 8.0 + 0.4 mIU/ml and 9.9 +/- 2.5 vs. 5.8 +/- 0.1 mIU/ml, respectively; P less than 0.01). These data support the hypothesis that T or one of its metabolites can modulate LH and FSH secretion independently of peripheral aromatization to E.


Assuntos
Estradiol/metabolismo , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Testosterona/farmacologia , Adulto , Estradiol/sangue , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Masculino , Testolactona/farmacologia , Testosterona/sangue , Testosterona/metabolismo
18.
J Clin Endocrinol Metab ; 53(4): 784-9, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6270173

RESUMO

To study the effects of catechol estrogens upon gonadotropin secretion, 2-hydroxyestrone (2-OHE1) and 2-hydroxyestradiol (2-OHE2) were administered iv to young adult men in a range of doses for 4 days. Blood samples were obtained for plasma LH, FSH, and PRL at 20-min intervals for 6 h before and at the end of the infusion period. 2-OHE1 had no effect upon gonadotropins or PRL in doses up to 1.6 mg/day; at 3.2 and 6.6 mg/day, it produced a slight suppression of LH and FSH, with no change in PRL. 2-OHE2 was generally ineffective at 100 micrograms/day, but doses from 200-800 micrograms/day suppressed gonadotropins, without changes in PRL. These infusions elevated 2-OHE1 and 2-OHE2 plasma levels to values comparable to those measured in late pregnancy. There were no associated effects upon blood pressure and only minimal changes in urinary catecholamine excretion. No effects that could be interpreted as antiestrogenic were observed. These results are consistent with the hypothesis that circulating catechol estrogens behave as weak estrogens in men.


Assuntos
Estrogênios de Catecol/farmacologia , Gonadotropinas Hipofisárias/sangue , Prolactina/sangue , Adulto , Catecolaminas/metabolismo , Relação Dose-Resposta a Droga , Estrogênios de Catecol/metabolismo , Humanos , Masculino , Receptores de Estrogênio/metabolismo
19.
J Clin Endocrinol Metab ; 56(6): 1243-5, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6841559

RESUMO

Primary cortisol resistance is an autosomal disease characterized by increased plasma cortisol concentration and high urinary free cortisol, resistance to adrenal suppression by dexamethasone, and the absence of clinical stigmata of Cushing's syndrome. The proband with the severe form had hypertension and hypokalemic alkalosis. In subjects with a less severe resistance to cortisol, there are no clinical abnormalities and the condition is revealed only by detailed examination of several parameters of cortisol secretion.


Assuntos
Hiperfunção Adrenocortical/genética , Hidrocortisona/urina , Hiperfunção Adrenocortical/sangue , Hiperfunção Adrenocortical/tratamento farmacológico , Dexametasona/uso terapêutico , Resistência a Medicamentos , Feminino , Humanos , Hidrocortisona/sangue , Masculino , Linhagem
20.
J Clin Endocrinol Metab ; 54(1): 150-4, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7054211

RESUMO

Plasma levels of 2-hydroxyestradiol (2-OHE2) were measured using a new RIA procedure. Values were below the detection limit of the assay (less than 10 pg/ml), except in the third trimester of pregnancy, when they rose to approximately 15 pg/ml. The infusion of 130 microgram/h purified 2-OHE2 elevated its plasma concentration to 155 pg/ml, consistent with a plasma MCR (MCRp) of approximately 20,000 liters/day. The infusion of [3H] 2-OHE2 to equilibrium and chromatographic separation of the extracted plasma metabolites yielded an MCRp of about 13,000 liters/day; the major plasma metabolite comigrated with 2-methoxyestradiol, and [3H] xi-methoxyestrone was also formed. The MCRp, of 2-OHE2 is approximately half that of 2-hydroxyestrone (2-OHE1), but much higher than those of other steroids. As is true for 2-OHE1, the clearance of 2-OHE2 must occur primarily in the blood compartment. Together, the measured MCRp values and estrogen receptor affinities of 2-OHE2 and 2-OHE1 predict a relative potency for effects upon gonadotropin secretion which is close to that observed in vivo.


Assuntos
Estradiol/análogos & derivados , 2-Metoxiestradiol , Adulto , Cromatografia por Troca Iônica , Cromatografia em Papel , Cromatografia em Camada Fina , Estradiol/sangue , Feminino , Meia-Vida , Humanos , Hidroxiestronas/sangue , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Radioimunoensaio
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