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1.
Artículo en Inglés | MEDLINE | ID: mdl-30877984

RESUMEN

Sensitive and accurate measurement of androstane-3ß,17ß-diol and androstane-3α,17ß-diol in the circulation is important for clinical research and accurate clinical diagnosis. This report describes a highly sensitive, specific, precise and reliable assay for the simultaneous accurate measurement of serum androstane-3α,17ß-diol and androstane-3ß,17ß-diol in postmenopausal women. The LLOQ of 1 pg/mL has been achieved with nicotinic acid derivatization, which is superior to picolinic acid by a factor of 5 to 10 in terms of signal to noise ratio. The difference is attributed to the higher acidity of picolinic acid which forms a more stable intermediate, thus decreasing derivatization efficiency. Potential interference from androstane-3α, 17α-diol, androstane-3ß, 17α-diol, and 5-androstenediol has been well separated from the two target diols. The high level of specificity has been determined by well-developed chromatography and ion ratio monitoring. A good linearity in the range of 1 pg/mL to 200 pg/mL (0.03 pg to 6 pg on column) was obtained for both compounds at R > 0.998. The bias and coefficients of variation of all the QC levels are within the range of 10% while the recovery in both charcoal-stripped and unstripped human serum is around 85%. The matrix effect was evaluated and the results well met the acceptance criteria according to the guidelines of bioanalytical method development and validation. Using this newly developed method, the concentrations of both androstane-3α,17ß diol and androstane-3ß,17ß diol were measured in normal postmenopausal serum, where the concentrations range from 2 pg/mL to 32 pg/mL for androstane-3α,17ß diol and from 1 pg/mL to 10 pg/mL for androstane-3ß,17ß diol, respectively.


Asunto(s)
Androstanos/sangre , Cromatografía Liquida/métodos , Posmenopausia/metabolismo , Espectrometría de Masas en Tándem/métodos , Femenino , Humanos , Límite de Detección , Modelos Lineales , Posmenopausia/sangre , Reproducibilidad de los Resultados
2.
BMC Public Health ; 8: 72, 2008 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-18294394

RESUMEN

BACKGROUND: Studies investigating the association of cadmium and sex steroid hormones in men have been inconsistent, but previous studies were relatively small. METHODS: In a nationally representative sample of 1,262 men participating in the morning examination session of phase I (1998-1991) of the third National Health and Nutrition Examination Survey, creatinine corrected urinary cadmium and serum concentrations of sex steroid hormones were measured following a standardized protocol. RESULTS: After adjustment for age and race-ethnicity, higher cadmium levels were associated with higher levels of total testosterone, total estradiol, sex hormone-binding globulin, estimated free testosterone, and estimated free estradiol (each p-trend < 0.05). After additionally adjusting for smoking status and serum cotinine, none of the hormones maintained an association with urinary cadmium (each p-trend > 0.05). CONCLUSION: Urinary cadmium levels were not associated with sex steroid hormone concentrations in a large nationally representative sample of US men.


Asunto(s)
Cadmio/orina , Estradiol/sangre , Prostatismo/sangre , Globulina de Unión a Hormona Sexual/análisis , Testosterona/sangre , Androstanos/sangre , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Fumar/sangre , Fumar/orina
3.
J Clin Invest ; 48(4): 696-703, 1969 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-5774107

RESUMEN

Metabolic clearance rates of testosterone (MCR(T)) and androstenedione (MCR(A)) were determined twice during the same cycle in six normal women, using a constant infusion of testosterone-(3)H and androstenedione-(14)C. Nonlabeled steroids served as internal standards. Plasma concentrations of testosterone (i(T)) and androstenedione (i(A)) were measured, and the blood production of testosterone (P(B) (T)) and of androstenedione (P(B) (A)) were calculated. The interconversions of these two steroids were also estimated. Six ovariectomized women were studied in the same manner. For testosterone, the mean i(T) in the normal women was not significantly different from that in the ovariectomized subjects, whereas the MCR(T) and P(B) (T) were significantly lower in the ovariectomized subjects. For androstenedione, the mean MCR(A) values of the two groups of subjects were not different, whereas the i(A) and P(B) (A) in the normal women were about double those in the ovariectomized subjects. In comparing the follicular and luteal phases of the menstrual cycle in four of six subjects there was no difference in i(T), MCR(T), or P(B) (T), whereas i(A), MCR(A), and P(B) (A) were increased in the luteal phase. In one ovariectomized woman infused with testosterone and androstenedione at physiologic levels, MCR(T) doubled but MCR(A) remained the same. After six wk on estrogen, the same subject did not show any change in MCR(T) after infusion of testosterone. It is suggested that MCR(T) depends on P(B) (T) and on plasma binding of testosterone which is partly estrogen dependent.


Asunto(s)
Andrógenos/sangre , Androstanos/sangre , Castración , Tasa de Depuración Metabólica , Ovario/fisiología , Testosterona/sangre , Adulto , Anciano , Isótopos de Carbono , Femenino , Humanos , Persona de Mediana Edad , Estadística como Asunto , Tritio
4.
J Clin Invest ; 54(3): 646-53, 1974 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-4855449

RESUMEN

Kinetics of 5alpha-androstane-3alpha, 17beta-diol (3alpha-diol) were studied in man. Clearance rates were determined by both the constant infusion and single injection techniques. Production rates were calculated as the product of clearance rate data and plasma values in the a.m. obtained by a radioimmunoassay specific for 3alpha-diol. Mean metabolic clearance rates were 1,776+/-492 (SD) liters/day in males and 1,297+/-219 (SD) liters/day in females. Metabolic clearance rates by single injection were similar. Calculated production rates are 208+/-26 (SD) mug/day in males and 35+/-11 mug/day in females, which are significantly different. Hepatic extraction of 3alpha-diol determined by hepatic vein catheterization during constant infusion was 76% which was greater than expected from information on in vitro binding in plasma. The kinetic data is of interest since 3alpha-diol has a calculated inner pool (V(1)) volume of 12-14 liters, similar to 17beta-hydroxyandrost-4-en-3-one (testosterone) and 5alpha-androstan-17beta-ol-3-one (dihydrotestosterone), but the calculated outer pool (V(2)) of 33.5 liters is very large as are the metabolic rate and transfer constant. In contrast to testosterone and dihydrotestosterone, 3alpha-diol, although bound to sex hormone binding globulin, has a high metabolic clearance of which a large fraction represents extrahepatic (splanchnic) metabolism. A production rate of 3alpha-diol similar to dihydrotestosterone together with rather unique kinetic characteristics encourages further investigation of the biological role of this potent androgen.


Asunto(s)
Androstanos/metabolismo , Abdomen/metabolismo , Androstanos/administración & dosificación , Androstanos/biosíntesis , Androstanos/sangre , Radioisótopos de Carbono , Femenino , Venas Hepáticas , Humanos , Infusiones Parenterales , Inyecciones Intravenosas , Cinética , Hígado/metabolismo , Circulación Hepática , Masculino , Radioinmunoensayo , Testosterona/administración & dosificación , Testosterona/metabolismo , Factores de Tiempo , Tritio
5.
J Clin Invest ; 50(6): 1338-44, 1971 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-5103749

RESUMEN

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.


Asunto(s)
Androstanos/sangre , Dihidrotestosterona/sangre , Dihidrotestosterona/metabolismo , Testosterona/metabolismo , Hiperfunción de las Glándulas Suprarrenales/cirugía , Adulto , Isótopos de Carbono , Coriocarcinoma/metabolismo , Cromatografía en Papel , Cromatografía en Capa Delgada , Etinilestradiol/uso terapéutico , Femenino , Fludrocortisona/uso terapéutico , Hirsutismo/metabolismo , Humanos , Hidrocortisona/uso terapéutico , Medroxiprogesterona/uso terapéutico , Tasa de Depuración Metabólica , Quistes Ováricos/metabolismo , Embarazo , Esteroles/sangre , Tritio
6.
Steroids ; 72(11-12): 792-801, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17716701

RESUMEN

Certain androstane steroids (AS) modulate ionotropic receptors, as do the pregnane steroids. Whereas women produce significant amounts of neuroactive progesterone metabolites, the steroid neuromodulators in men originate mainly from the 3-oxo-4-ene C(19)-steroids, which are converted to their 3alpha- and 3beta-hydroxy-5alpha/5beta-reduced metabolites. The neuromodulating effects of AS prompted us to monitor circulating levels of the steroids to estimate metabolic pathways in the periphery that may influence brain concentrations of AS. Hence, the serum levels of 20 steroids and 16 steroid polar conjugates including 17-oxo- and 17beta-hydroxy-derivatives of 5alpha/beta-androstane-3alpha/beta-hydroxy-androstane steroids were quantified in 15 men (16-62 years of age) using GC-MS. The conjugated AS for the most part reached micromolar concentrations, these being two or three orders of magnitude higher than those of the free steroids. The ratios of conjugates to free steroids were one to two orders of magnitude higher than the values for the corresponding pregnane steroids. This data suggested that conjugation may considerably restrain the transport of free AS from the periphery into the central nervous system.


Asunto(s)
Androstanos/sangre , Cromatografía de Gases y Espectrometría de Masas/métodos , Adolescente , Adulto , Androstanos/química , Androstenodiona/química , Humanos , Masculino , Persona de Mediana Edad , Pregnanos/sangre , Presión , Temperatura , Testosterona/química , Compuestos de Trimetilsililo/análisis
7.
J Clin Endocrinol Metab ; 90(10): 5647-55, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16030154

RESUMEN

CONTEXT: Combination of a GnRH antagonist (acyline), types I and II, 5alpha-reductase inhibitor (dutasteride) or levonorgestrel (LNG) with testosterone (T) treatment may augment the suppression of spermatogenesis and intratesticular (iT) steroids. OBJECTIVE: The objective of this study was to assess the effects of combined hormonal contraceptive regimens on germ cell populations and iT steroids. DESIGN, SETTING, AND PARTICIPANTS: Twenty-nine normal health men enrolled in this prospective, randomized, 14-wk study at the University of Washington. INTERVENTION(S): Twenty-two men (n = 5-6/group) received 8 wk of T enanthate (TE; 100 mg, i.m., weekly) combined with 1) 125 microg LNG daily, orally; 2) 125 microg LNG plus 0.5 mg dutasteride daily, orally; 3) 300 microg/kg acyline twice weekly, s.c.; or 4) 125 microg LNG daily, orally, plus 300 microg/kg acyline twice weekly, s.c. Subjects then underwent a vasectomy and testicular biopsy. Control men (n = 7) proceeded directly to surgery. MAIN OUTCOME MEASURE(S): The main outcome measures were germ cells and iT steroids [T, dihydrotestosterone, 3alpha- and beta-androstanediol (Adiol), and estradiol (E2)]. RESULTS: High iT levels of all androgens (6- to 123-fold serum levels) and E2 (407-fold serum levels) were found in control men. iTT (1.9-2.6% control; P < 0.001) and iT3betaAdiol (16-34% control; P < 0.05) levels decreased with all treatments. iT dihydrotestosterone (13-29% control; P < 0.05) and iT3alphaAdiol (44-47% control; P < 0.05) levels decreased with all but the TE plus LNG treatment. iTE2 levels decreased only in the TE plus acyline group (28% control; P = 0.01). Germ cells from type B spermatogonia onward were suppressed, with no differences between groups found. Variable sites of impairment of germ cell progression were evident between men (spermagonial maturation, meiosis 1 entry, and spermiation). Other than a negative correlation between iT3alphaAdiol and haploid germ cell number (P < 0.006), no correlations between germ cell number and gonadotropins, sperm concentration, or iT steroids were found. CONCLUSIONS: A similar high testicular:serum gradient exists for E2 and T in normal men, and 8 wk of gonadotropin suppression markedly reduces iTT, with 5alpha-reduced androgens and E2 levels decreasing to a much lesser degree. The heterogeneity of the germ cell response, regardless of treatment, gonadotropins or iT steroids, points to the individual sensitivity of sites in germ cell development, which is worthy of additional exploration.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Inhibidores Enzimáticos/farmacología , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Levonorgestrel/farmacología , Congéneres de la Progesterona/farmacología , Espermatogénesis/efectos de los fármacos , Esteroides/metabolismo , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/farmacología , Adulto , Androstanos/sangre , Azaesteroides/farmacología , Dihidrotestosterona/sangre , Dutasterida , Estradiol/sangre , Células Germinativas/efectos de los fármacos , Humanos , Masculino , Estudios Prospectivos , Células de Sertoli/efectos de los fármacos , Testosterona/sangre , Vasectomía
8.
Endocrinology ; 100(4): 1027-32, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-837871

RESUMEN

Serum concentrations of testosterone plus dihydrotestosterone (T-DHT), 5 alpha-androstane-3 alpha, 17 beta-diol (Diol) and androsterone were measured during sexual maturation in male rats. Diol concentrations of 1 to 2.25 ng/ml were found in animals 10-90 days of age with no significant changes. Diol was the major androgen (5.75-8 times T-DHT) from age 20-40 days. Androsterone rose to 1.25 ng/ml at 25 days of age and declined to values of greater than 0.5 ng/ml from age 30-90 days. Testosterone-DHT levels were 1 ng/ml or less from 10-40 days of age, and then rose to a peak at 60 days. The ratio of Diol toT-DHT was significantly elevated from age 20-35 days, indicating that Diol is the major androgen in circulation at this time. Acute treatment of 33 day old rats with LH, but not with FSH, resulted in a dose-dependent increase in serum T-DHT, Diol, and androsterone. The dose-response and time course of response for the three steriods were nearly identical. Changes in testes capacity to secrete androgens were assessed 25, 33, 40 and 60 days of age by administering a maximum dose of LH before blood collection. Maximum response (sum of androsterone, Diol and T-DHT) occurred at 40 days with no further increase at 60 days.


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Androsterona/sangre , Hormona Luteinizante/farmacología , Testosterona/sangre , Envejecimiento , Animales , Dihidrotestosterona/sangre , Hormona Folículo Estimulante/farmacología , Masculino , Ratas , Maduración Sexual
9.
Endocrinology ; 97(4): 787-92, 1975 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1193006

RESUMEN

A simultaneous radioimmunoassay procedure for plasma testosterone (T), 5alpha-androstan-17beta-ol-3-one (DHT), 5alpha-androstane-3alpha,17beta-diol (3alphaol), and 5alpha-androstan-3beta,17beta-diol (3betaol) is described in this report. Peripheral plasma concentrations of T, DHT, 3alphaol, and 3betaol were 1.16 +/- 0.26, 0.49 +/- 0.15, 0.17 +/- 0.03, and 0.24 +/- 0.04 ng/ml, respectively, in adult male rabbits. In contrast, T, DHT, 3alphaol, and 3betaol peripheral plasma concentrations in dexamethasone-treated castrate rabbits were 0.07 +/- 0.01, 0.02 +/- 0.01, 0.07 +/- 0.01, and 0.05 +/- 0.01 ng/ml, respectively. These results represent the first simultaneous measurement of T, DHT, 3alphaol, and 3betaol in peripheral plasma of any male vertebrate. Moreover, we suggest that DHT, 3alphaol, and 3betaol represent the unidentified immunoreactive material found in peripheral plasma of male rabbits by Falvo and Nalbandov (1).


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Dihidrotestosterona/sangre , Radioinmunoensayo/métodos , Testosterona/sangre , Animales , Castración , Cromatografía en Gel , Dexametasona/farmacología , Masculino , Conejos
10.
J Endocrinol ; 71(3): 299-304, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1003060

RESUMEN

The conjugation of 5alpha-androstane-3alpha,17beta-diol (3alpha-A) and its 3beta epimer (3beta-A) was determined in the peripheral blood of immature female rats. About two thirds of these steroids were present in blood as sulphates and one third as glucuronides; no free steroids were detected. Administration of 3beta-A sulphate (25mug/100 g body weight/day) and of 3alpha-A sulphate (50 mug/100 g/day) from day 21 of life until the day of vaginal opening, advanced the day of the first ovulation. Administration of the 3beta-A sulphate did not induce precocious vaginal opening whereas the free alcohol was active in this respect. Implantation of 3beta-A sulphate, but not of the 3alpha epimer, into the basal medial hypothalamus resulted in the dealth of all animals within 24 h.


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/farmacología , Animales , Implantes de Medicamentos , Femenino , Ovulación/efectos de los fármacos , Ratas , Factores de Tiempo
11.
Obstet Gynecol ; 53(1): 111-5, 1979 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-215946

RESUMEN

The peripheral levels of 17-hydroxypregnenolone (17delta5P), progesterone (P), 17-hydroxyprogesterone (17P), testosterone (T), 5alpha-dihydrotestosterone (DHT), androstenedione (A), androst-5-ene-3beta,17beta-diol (delts5diol), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), estradiol-17beta (E2), and cortisol (F) were measured in peripheral and right adrenal venous blood of an amenorrheic patient with a right virilizing adrenal adenoma. Urinary 17-ketosteroids were markedly elevated and were not suppressed on a low dose of dexamethasone (Dex) for 7 days. Peripheral T level was 1.2 ng/ml and DHEA-S was 13,500 ng/ml. Calculations of the ratios of adrenal venous gradients for delta5 and delta4 steroids suggest that the predominant pathway of steroid secretion used by the tumor was as follows: pregnenolone (delta5P) leads to 17delta5P leads to DHEA leads to A leads to T. Following removal of the adenoma, T returned to normal levels but DHEA-S was still above normal at 4100 ng/ml. The patient became eumenorrheic with marked improvement at her hirsutism and virilization.


Asunto(s)
17-Hidroxicorticoesteroides/sangre , Adenoma/sangre , Neoplasias de las Glándulas Suprarrenales/sangre , Androstanos/sangre , Hormonas Esteroides Gonadales/sangre , 17-alfa-Hidroxipregnenolona/sangre , Adenoma/metabolismo , Adolescente , Neoplasias de las Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/irrigación sanguínea , Androstenodioles/sangre , Androstenodiona/sangre , Deshidroepiandrosterona/sangre , Dihidrotestosterona/sangre , Estradiol/sangre , Femenino , Humanos , Hidrocortisona/sangre , Hidroxiprogesteronas/sangre , Testosterona/sangre , Venas
12.
Obstet Gynecol ; 53(1): 36-43, 1979 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-215947

RESUMEN

The ovarian-peripheral gradients of various delta4 and delta5 steroids were determined for a patient with virilizing arrhenoblastoma. The high peripheral testosterone level accompanying this tumor results from increased precursor supply from both the delta4 and delta5 pathways, with the delta5 pathway predominating, and from negligible aromatase activity. A review of 45 cases of androgen-producing ovarian tumors with measurement of peripheral venous testosterone, and of 24 cases with measurement of ovarian venous testosterone, and a comparison with findings in 159 patients with hirsutism of functional origin reveal the following 1) An androgen-producing tumor must be ruled out when peripheral testosterone exceeds 2 ng/ml; 2) an ovarian venous testosterone level exceeding 20 ng/ml generally accompanies a tumor, particularly when the tumor is less than 5 cm in diameter; and 3) virtually all (98%) of the tumors reviewed were accompanied by virilization, regardless of the peripheral concentration of testosterone.


Asunto(s)
17-Hidroxicorticoesteroides/sangre , Androstanos/sangre , Hormonas Esteroides Gonadales/sangre , Neoplasias Ováricas/sangre , Ovario/irrigación sanguínea , Tumor de Células de Sertoli-Leydig/sangre , 17-Hidroxicorticoesteroides/biosíntesis , 17-alfa-Hidroxipregnenolona/sangre , Androstanos/biosíntesis , Androstenodioles/sangre , Androstenodiona/sangre , Deshidroepiandrosterona/sangre , Dihidrotestosterona/sangre , Estradiol/sangre , Femenino , Hormonas Esteroides Gonadales/biosíntesis , Humanos , Hidrocortisona/sangre , Persona de Mediana Edad , Progesterona/sangre , Testosterona/sangre , Venas
13.
Fertil Steril ; 27(9): 1101-4, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-964402

RESUMEN

A rapid and relatively simple, but specific, radioimmunoassay for the potent androgen, androstanediol (3 alpha-diol), is described. Despite the availability of a nonspecific C-19 androgen antibody requiring a 17 beta-hydroxy group, androstanediol can be measured in plasma by prior purification of a plasma solvent extract using a Celite microcolumn. Values obtained do not differ from those previously reported using more complicated chromatographic techniques.


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Cromatografía/instrumentación , Radioinmunoensayo/métodos , Androstano-3,17-diol/inmunología , Femenino , Humanos , Masculino
14.
Steroids ; 32(1): 61-71, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-705818

RESUMEN

The simultaneous determinations of both 3alpha and 3beta epimers of 5alpha-androstane-3,17beta-diol as their glucuronides, sulfates and in their unconjugated forms are described. The diol estimation is carried out by radioimmunoassay with two specific immune sera after purification of the serum by use of chromatography on Sephadex LH-20. The values obtained (mean +/- S.D.) in pg/ml for the unconjugated 3alpha and 3beta epimers were, respectively, 267 +/- 67 and 816 +/- 76 for men; 114 +/- 33 and 515 +/- 177 for women; 142+/- 77 and 779 +/- 200 for hirsute women. Among the conjugates, the most important were the sulfoconjugates, their rates being, respectively (men +/- S.D. in ng/ml 41.6 +/- 9.5 and 103+/- 40 for men; 12.4 +/- 3.1 and 51.2 +/- 14.9 for women and 36 +/- 22 and 72 +/- 36 for hirsute women. Differences in the conjugation of both epimers were also noticed.


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Adolescente , Adulto , Especificidad de Anticuerpos , Cromatografía en Gel , Cromatografía en Capa Delgada , Femenino , Hirsutismo/sangre , Humanos , Hidrólisis , Métodos , Embarazo , Radioinmunoensayo , Estereoisomerismo
15.
Steroids ; 29(4): 503-16, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-867448

RESUMEN

A single thin layer chromatography and three antibodies were used for the specific radioimmunoassay of four androgens in pooled rat plasma (Sprague-Dawley adult males). The following values were found (pg/ml +/- SD). Testosterone: 3, 138 +/-173; dihydrotestosterone: 374 +/-20; 5alpha-androstane-3alpha, 17beta-diol: 284+/-24; 5alpha-androstane-3beta, 17beta-diol: 223+/-11.


Asunto(s)
Androstano-3,17-diol/sangre , Androstanos/sangre , Dihidrotestosterona/sangre , Testosterona/sangre , Animales , Estudios de Evaluación como Asunto , Masculino , Métodos , Radioinmunoensayo , Ratas
16.
Steroids ; 57(2): 76-81, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1621260

RESUMEN

In humans, the onset of adrenache has been found to occur with the appearance of the zona reticularis, the inner zone of the adrenal cortex. Since an increase in the volume of adrenal cortex during maturation in the guinea pig has been associated with the growth of the zona reticularis, we were interested in investigating the changes in adrenal steroidogenesis during maturation in this species. In addition, the effect of androgens on adrenal steroidogenesis was studied. We demonstrated that between 1 and 10 weeks of age, a period of maximal growth of the adrenals in the guinea pig, there is a decrease in the concentrations of adrenal pregnenolone, cortisol, dehydroepiandrosterone, testosterone, androstenedione, and 11 beta-hydroxyandrostenedione, suggesting lower steroid production by the guinea pig adrenals. In plasma, we observed that the concentration of 11 beta-hydroxyandrostenedione (the sole C19 steroid present after castration) remained unchanged during maturation, while cortisol and corticosterone were lower between 1 and 4 weeks of age. Although castration as well as the administration of the antiandrogen flutamide had no effect on adrenal steroidogenesis, dihydrotestosterone caused an inhibition of cortisol and corticosterone levels in the adrenals while the concentrations of progestins (namely, pregnenolone, 17-hydroxypregnenolone, progesterone, and 17-hydroxyprogesterone) tended to increase in the adrenals, thus suggesting that dihydrotestosterone induces a blockade in the steroidogenic pathway.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Corteza Suprarrenal/metabolismo , Dihidrotestosterona/farmacología , Esteroides/biosíntesis , Zona Reticular/metabolismo , Corteza Suprarrenal/crecimiento & desarrollo , Androstanos/sangre , Androstanos/metabolismo , Animales , Castración , Flutamida/farmacología , Cobayas , Masculino , Pregnenos/sangre , Pregnenos/metabolismo , Radioinmunoensayo , Esteroides/sangre , Zona Reticular/crecimiento & desarrollo
17.
Bull Cancer ; 78(7): 611-8, 1991.
Artículo en Francés | MEDLINE | ID: mdl-1912672

RESUMEN

We describe the effect of 12 C19-steroids on human breast cancer hormono-dependent cell growth. 5-Androstene-3 beta, 17 beta diol and 5 alpha-androstane-3 beta, 17 beta diol are the most mitogenic Dehydroepiandrosterone, 5 beta-androstane-3 beta, 17 beta diol and the two 5-androstane-3 alpha, 17 beta diol are less mitogenic. 5 alpha-Dihydrotestosterone and testosterone have no effect at physiologic doses, but can modulate MCF-7 growth at pharmacologic concentrations. Androsterone and etiocholanolone have no effect, whereas androstenedione inhibits MCF-7 cell growth.


Asunto(s)
Androstanos/farmacología , Neoplasias de la Mama/patología , Neoplasias Hormono-Dependientes/patología , Células Tumorales Cultivadas/efectos de los fármacos , Androstanos/sangre , Neoplasias de la Mama/sangre , Estradiol , Femenino , Humanos , Menopausia/sangre , Neoplasias Hormono-Dependientes/sangre
18.
Urologe A ; 18(6): 311-5, 1979 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-388799

RESUMEN

The most reliable laboratory test for prostate cancer remains prostatic phosphatase determination. With the spectrophotometric method, however, falsely negative results are to be expected in 40% of stage D lesions. In only one third of patients with localized disease results are correctly positive. This poor specificity and sensitivity can be improved by radioimmunoassay (RIA). Using this technique the prostatogenic isoenzyme is elevated in 50% of stage A and in 80% of stage B carcinoma, suggesting RIA for screening. Erythrocyte sedimentation rate or serum iron and copper are not necessarily of prognostic value. Phosphatase determination of bone marrow aspirates also requires the RIA method if differentiation of stage C and D is to be expected. Serum hormone assays are not yet introduced into routine staging programs. Serum and urinary markers such as CEA, polyamines of LDH isoenzymes are unspecific and of uncertain value in prostatic carcinoma. Measurement of urinary hydroxyproline seems a reliable method for the search of osseous spread; other bone diseases have to be excluded. In patients with prostate cancer laboratory tests still represent adjunctive measures in connection with the clinical diagnostic armamentarium of urologists.


Asunto(s)
Neoplasias de la Próstata/diagnóstico , Fosfatasa Ácida/análisis , Fosfatasa Alcalina/análisis , Androstanos/sangre , Médula Ósea/enzimología , Antígeno Carcinoembrionario/análisis , Reacciones Falso Negativas , Humanos , Hidroxiprolina/orina , Isoenzimas/análisis , Isoleucina/orina , Masculino , Poliaminas/orina , Neoplasias de la Próstata/enzimología , Radioinmunoensayo
19.
Steroids ; 76(12): 1351-7, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21787799

RESUMEN

BACKGROUND: Epilepsy in women may be associated with reproductive disorders and alterations in serum steroid levels. Some steroids can be induced by epilepsy and/or treatment with antiepileptic drugs; however, there are still limited data available concerning this effect on the levels of other neuroactive steroid metabolites such as 3a-hydroxy-5a/b-reduced androstanes. AIM: To evaluate steroid alterations in women with epilepsy (WWE) on lamotrigine monotherapy. SUBJECTS AND METHODS: Eleven WWE and 11 age-matched healthy women underwent blood sampling in both phases of their menstrual cycles (MCs). The steroid metabolome, which included 30 unconjugated steroids, 17 steroid polar conjugates, gonadotropins, and sex hormone-binding globulin (SHBG), was measured using gas chromatography-mass spectrometry (GC-MS) and radioimmunoassay (RIA). RESULTS: WWE had lower cortisol levels (status p<0.001), but elevated levels of unconjugated 17-hydroxypregnenolone (status p<0.001). Progesterone was higher in the follicular menstrual phase (FP) in WWE than in the controls (status×menstrual phase p<0.05, Bonferroni multiple comparisons p<0.05), whereas 17-hydroxyprogesterone was higher in WWE in both menstrual phases (status p<0.001). The steroid conjugates were mostly elevated in WWE. The levels of 5α/ß-reduced androstanes in WWE that were significantly higher than the controls were etiocholanolone (status p<0.001), 5α-androstane-3α,17ß-diol (status p<0.001), and the 5α/ß-reduced androstane polar conjugates (status p<0.001). CONCLUSIONS: WWE showed a trend toward higher circulating 3α-hydroxy-5α/ß-reduced androstanes, increased activity of 17α-hydroxylase/17,20 lyase in the Δ(5)-steroid metabolic pathway, and increased levels of the steroid polar conjugates.


Asunto(s)
17-alfa-Hidroxipregnenolona/sangre , Androstanos/sangre , Androstanos/metabolismo , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Epilepsia/metabolismo , Triazinas/uso terapéutico , Adulto , Androstanoles/sangre , Anticonvulsivantes/efectos adversos , Femenino , Humanos , Lamotrigina , Metaboloma , Esteroide 17-alfa-Hidroxilasa/sangre , Triazinas/efectos adversos
20.
J Steroid Biochem Mol Biol ; 122(4): 239-52, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20541012

RESUMEN

Only limited data is available concerning the role of unconjugated Δ(5) C19-steroids and almost no data exists regarding the neuroactive C21 and C19 3α-hydroxy-5α/ß-metabolites in men with epilepsy. To evaluate the alterations in serum neuroactive steroids and related substances in adult men with epilepsy on valproate and carbamazepine monotherapy, we have measured 26 unconjugated steroids, 18 steroid polar conjugates, gonadotropins and sex hormone binding globulin (SHBG) in 6 and 11 patients on valproate and carbamazepine monotherapy, respectively, and in 19 healthy adult men, using the GC-MS and immunoassays. Decreased testosterone, free androgen index, free testosterone, androstenediol, 5α-androstane-3α,17ß-diol (androstanediol), androsterone, epiandrosterone, DHEA, 7ß-hydroxy-DHEA, and DHEAS levels were associated with epilepsy per se. Valproate (VPA) therapy increased 5α-dihydrotestosterone, androsterone, epiandrosterone, DHEA, DHEAS, and 7ß-hydroxy-DHEA levels. Decrease in pregnenolone and 17-hydroxypregnenolone were associated with epilepsy with no effect of antiepileptic drugs (AEDs). Alternatively, the increase in progesterone levels was linked to epilepsy and VPA further increased progesterone levels. Reduced steroid 20α-hydroxy-metabolites and cortisol were connected with epilepsy without an effect of AEDs. Carbamazepine induced only slight decrease in isopregnanolone, 5α,20α-tetrahydroprogesterone, and androstanediol levels.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Carbamazepina/uso terapéutico , Epilepsia/tratamiento farmacológico , Esteroides/sangre , Ácido Valproico/uso terapéutico , Adulto , Androstanos/sangre , Cromatografía de Gases y Espectrometría de Masas , Gonadotropinas/sangre , Humanos , Masculino , Pregnenolona/sangre , Globulina de Unión a Hormona Sexual/metabolismo , Esteroides/metabolismo , Testosterona/análogos & derivados , Testosterona/sangre
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