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2.
J Steroid Biochem Mol Biol ; 104(1-2): 85-91, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17208439

ABSTRACT

Rules of horse racing stipulate that pregnant mares may compete under definite conditions of date, because early pregnant status may be misused for the sake of enhancing physical performance by putative anabolic steroid action. Screening for pregnancy is generally performed by plasma equine gonadotrophin (eCG) immunoassay, which covers the period between Days 40 and 120. In common screening for urinary anabolic steroids performed by gas chromatography-mass spectrometry, inclusion of two complementary criteria, i.e. the evaluation of total conjugates of 5(10)-estrene-3beta,17alpha-diol (EED) and estrone (E1), can easily be performed. Although EED and E1 have no anabolic property per se in the horse, assessing these two markers may be helpful in the period comprised between Days 70 and 250, thereby prolonging the detection period behind that of eCG. Peak values of EED and E1 are then attained, so that visual inspection of chromatographic tracings remains in general sufficient as a diagnostic tool. Comparison of EED and E1 during pregnancy and in an estrus cycle indicates a drastic difference in the attained excretion values, attributable to either the placenta or the ovarian follicle. The identity of EED has been proven by GC-MS(n) in urine and in placental tissue.


Subject(s)
Anabolic Agents/urine , Estrenes/urine , Estrone/urine , Horses/urine , Animals , Doping in Sports , Female , Gas Chromatography-Mass Spectrometry , Placenta , Pregnancy
3.
Maturitas ; 46(3): 165-71, 2003 Nov 20.
Article in English | MEDLINE | ID: mdl-14585519

ABSTRACT

OBJECTIVES: To determine if the vascularisation of the endometrium is dependent on the administered progestin during sequential hormone replacement therapy. METHODS: Nine women received percutaneous estradiol-17 beta, 1.5 mg/day from days 1 to 24 combined with 200 mg/day micronised progesterone from days 11 to 24 of the treatment cycle. Fifteen women received percutaneous estradiol, 1.5 mg/day from days 1 to 24, combined with 10 mg/day chlormadinone acetate from days 11 to 24. Eleven women received percutaneous estradiol, 50 microg/day from days 1 to 28 combined with percutaneous norethisterone acetate, 0.3mg/day form days 14 to 28. Twelve women received intranasal estradiol, 300 microg/day from days 1 to 25 combined with 0.5 mg of promegestone from days 11 to 24. Eleven spontaneous cycling women had an endometrial biopsy during luteal phase and served as controls. Endometrial biopsies were processed routinely between days 18 and 24 and sections were immunostained using anti-CD34 antibody to identify vascular endothelial cells, which were treated with an automatic image analysis system. RESULTS: mean (+/-S.D.) vascular density for controls was 147+/-41.5 vessels/mm(2), with mean vessel area of 143+/-60.9 microm(2). In chlormadinone users endometrial microvascular density and mean vessel area did not differ from the control group (150.2+/-58.6 and 152.9+/-70.5). The other three progestins generated a significant increase of mean vessel density, 179.6+/-51.6 with micronised progesterone, 178.5+/-67.6 with norethisterone and 179.6+/-48.4 with promegestone. The mean vessel area was lower in the latter three groups, respectively, 108.4+/-39.0, 97.5+/-46.5 and 141.6+/-66.7 microm(2), promegestone leading to non significant difference with control. CONCLUSION: regarding vascularisation, chlormadinone and control group gave similar patterns. Promegestone was associated with an increase of the number of vessels, as did micronised progesterone or norethisterone; the mean vascular area was the smallest in the norethisterone group.


Subject(s)
Chlormadinone Acetate/pharmacology , Endometrium/drug effects , Estradiol/pharmacology , Norethindrone/pharmacology , Postmenopause , Progesterone/pharmacology , Promegestone/pharmacology , Administration, Cutaneous , Administration, Intranasal , Case-Control Studies , Chlormadinone Acetate/administration & dosage , Drug Administration Schedule , Endometrium/blood supply , Endometrium/pathology , Estradiol/administration & dosage , Female , Humans , Image Processing, Computer-Assisted , Immunohistochemistry , Microcirculation/drug effects , Middle Aged , Norethindrone/administration & dosage , Progesterone/administration & dosage , Promegestone/administration & dosage
4.
Article in English | MEDLINE | ID: mdl-11824814

ABSTRACT

The dietary supplements 19-norandrostenedione and 19-norandrostenediol are potential metabolic precursors of nandrolone. They are considered by law in the United States as prohormones without proven therapeutic, curative or diagnostic properties, and therefore available as over-the-counter drugs. Oral dosages of 0.1-1 mg/kg body weight were readily absorbed in the equine intestinal tract and thereby led to urinary excretion of drastically increased 5alpha-estrane-3beta,17alpha-diol conjugates, which are known to be final metabolites of nandrolone. The actual rules for detection of illicit nandrolone administration to the horse have been found applicable for the detection of surreptitious oral 19-norandrostenedione and 19-norandrostenediol supplementation. Secondary markers of these administrations were high-level excretions of conjugated nandrolone, epinandrolone, 19-noretiocholanolone and 19-norepiandrosterone. No significant increase of circulating, biologically active nandrolone could be firmly evidenced, and it is therefore unclear to what extent continuous long-term administrations may have anabolic action.


Subject(s)
Androstenediol/metabolism , Androstenedione/metabolism , Dietary Supplements , Doping in Sports , Androstenediol/blood , Androstenediol/urine , Androstenedione/analogs & derivatives , Androstenedione/blood , Androstenedione/urine , Animals , Horses , Humans
5.
J Clin Endocrinol Metab ; 86(1): 146-50, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11231992

ABSTRACT

19-Nortestosterone (nandrolone) is an anabolic steroid compound widely used as a doping agent by athletes. The analysis of its urinary metabolites, 19-norandrosterone (NA) and 19-noretiocholanolone (NE) glucuronides, allows the detection of surreptitious administration of nandrolone in sport. A threshold concentration at 2 microgram/L urinary nandrolone metabolites is advocated by the International Olympic Committee for the detection of doping, but some controversy concerning the validity of this threshold arose from the demonstration of endogenous production of nandrolone in mammals, including humans. The regulation of human nandrolone production and its contribution in vivo to the process of aromatization remain unknown. In the present study 10 healthy men were successively submitted to insulinic stress and gonadal stimulation by hCG administration. Urinary NA and NE concentrations were quantified by gas chromatography-mass spectrometry. NA was detected in basal urine samples from all subjects, with a mean urinary excretion rate (UER) of 3.17 +/- 0.35 ng/h, whereas NE was detected in 4 of 10 (UER range, 0.8-4.7 ng/h). Insulinic hypoglycemia did not significantly modify mean NA UER despite random intraindividual variations between timed urine collections. After hCG administration, NA UER increased by 250% (P < 0.01) and estradiol (E(2)) UER by 260% (P < 0.001). The maximum NA concentration obtained after stimulation was 0.43 microgram/L. NA UER, plasma E(2), and E(2)/T ratio peaked on day 1 after hCG administration, whereas plasma T peaked later on day 3. NA UER correlated with plasma E(2) (r = 0.61; P < 0.001) and E(2)/T (r = 0.51; P < 0.001), but not with plasma T. In conclusion, insulinic stress did not significantly alter nandrolone metabolism, whereas the effect of hCG was a stimulation of NA excretion in all subjects, which constitutes strong support for the endogenous origin of low basal NA excretion. The comparative kinetics of NA UER, plasma E(2), and E(2)/T ratio suggest a contribution of the aromatase process to nandrolone biosynthesis in man.


Subject(s)
Chorionic Gonadotropin/pharmacology , Nandrolone/metabolism , Adult , Estradiol/blood , Estranes/blood , Estranes/urine , Humans , Hypoglycemia/complications , Male , Stress, Physiological/etiology , Stress, Physiological/urine , Testosterone/blood
6.
Biol Reprod ; 64(3): 812-21, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11207196

ABSTRACT

The status of the corticosteroid-binding globulin (CBG) at the fetomaternal interface, especially in the maternal intervillous blood space (I), was investigated and compared to that of CBG in the maternal (M) and fetal (umbilical arteries [A] and vein [V]) peripheral circulations at term. Immunoquantitation of plasma CBG showed that the CBG concentration in I was 30% less than that in M (P < 0.001) and threefold higher than that in umbilical cord blood (P < 0.001). The microheterogeneity of CBG studied by immunoaffinoelectrophoresis in the presence of concanavalin A and Western blotting indicated that the CBG in I was mainly of maternal origin and different from fetal CBG. A CBG mRNA, but no classic 50- to 59-kDa CBG, was found in isolated term trophoblastic cells. The steroid environment of the CBG in I differed greatly from that in the peripheral maternal and fetal circulations, because the progesterone:cortisol molar ratio in I was 75-fold higher than that in M and 7- to 10-fold higher than that in the fetal circulation. Binding studies revealed that the affinity constants of CBG for cortisol in I, A, and V were significantly lower than that in M plasma (P < 0.02) in their respective hormonal contexts. The binding parameters for I-CBG stripped of endogenous steroids and lipids were close to those for M-CBG but different from those of fetal CBG (P < 0.001). These data reflect the physiological relevance of the CBG-steroid interaction, especially with very CBG-loaded progesterone at the fetomaternal interface during late pregnancy.


Subject(s)
Fetal Blood/metabolism , Maternal-Fetal Exchange/physiology , Placenta/metabolism , Pregnancy/metabolism , Transcortin/metabolism , Adult , Blotting, Western , Cesarean Section , Enzyme-Linked Immunosorbent Assay , Female , Fetal Blood/physiology , Gas Chromatography-Mass Spectrometry , Humans , Hydrocortisone/blood , Immunoelectrophoresis, Two-Dimensional , Immunomagnetic Separation , Male , Placenta/physiology , Pregnancy/blood , Progesterone/blood , Protein Isoforms , Radioimmunoassay , Reverse Transcriptase Polymerase Chain Reaction , Serum Albumin/metabolism , Transcortin/physiology , Trophoblasts/metabolism , Trophoblasts/physiology
7.
J Anal Toxicol ; 25(8): 685-90, 2001.
Article in English | MEDLINE | ID: mdl-11765025

ABSTRACT

Dehydroepiandrosterone (DHEA) and androstenedione are weak androgens, which need conversion to more potent testosterone in order to enhance anabolic action. Consequences of oral dosing at 1 mg/kg on the urinary and plasma androgen profile of mare and gelding have been evaluated with an analytical method involving conjugate fractionation and selective hydrolysis, group separation, and quantitation by gas chromatography-mass spectrometry with selected ion monitoring of trimethylsilyl ethers. Peak levels of testosterone total conjugates in urine (range 300-6000 microg/L) were attained a few hours after dosing. Renal clearance was fast, so the testosterone detection period lasted only 20 to 33 h, the longest time being generated by androstenedione. The urinary testosterone/epitestosterone ratio for detection of exogenous testosterone in the mare was inoperative after DHEA administration because there was a concomitant increase of epitestosterone, which thereby acted as a masking agent. Androstanediols and androstenediols, as well as some 17-ketosteroids, were additional markers. A transient increase of circulating free testosterone has been evidenced, and this would support possible anabolic/androgenic action by supplementation with DHEA and androstenedione along the oral route.


Subject(s)
Adjuvants, Immunologic/blood , Androstenedione/blood , Dehydroepiandrosterone/blood , Doping in Sports , Horses/physiology , Adjuvants, Immunologic/administration & dosage , Adjuvants, Immunologic/pharmacokinetics , Adjuvants, Immunologic/urine , Administration, Oral , Androstenedione/administration & dosage , Androstenedione/pharmacokinetics , Androstenedione/urine , Animals , Biomarkers/analysis , Dehydroepiandrosterone/administration & dosage , Dehydroepiandrosterone/analysis , Dehydroepiandrosterone/pharmacokinetics , Dehydroepiandrosterone/urine , Female , Gas Chromatography-Mass Spectrometry , Male , Urinalysis/veterinary
8.
J Chromatogr B Biomed Sci Appl ; 721(2): 301-7, 1999 Jan 22.
Article in English | MEDLINE | ID: mdl-10052703

ABSTRACT

A GC-MS method, using deuterium-labelled 19-noretiocholanolone as internal standard and following an extensive LC purification prior to selected ion monitoring of the bis(trimethylsilyl) ethers at ion masses m/z 405, 419, 420 and 421, allowed the quantitation of subnanogram amounts of 19-norandrosterone present in 10-ml urine samples at m/z 405. Thirty healthy men, free of anabolic androgen supply, delivered 24-h urine collections in 4 timed fractions. Accuracy was proven by the equation, relating added (0.05-1 ng/ml) to measured analyte, which had a slope not significantly different from 1. Precision (RSD) was 4% at a concentration of 0.4 ng/ml, and 14% at 0.04 ng/ml. Analytical recovery was 82%. The limit of quantitation was 0.02 ng/ml. The excretion ranges were 0.03-0.25 microg/24 h or 0.01-0.32 ng/ml in nonfractionated 24-h urine. Taking into account inter-individual variability and log-normal distribution, a threshold of 19-norandrosterone endogenous concentration of 2 ng/ml, calculated as the geometric mean plus 4 SD, was established. This value corresponds to the decision limit advised by sport authorities for declaring positive (anabolic) doping with nandrolone.


Subject(s)
Doping in Sports , Estranes/urine , Substance Abuse Detection/methods , Adolescent , Adult , Chromatography, Ion Exchange , Chromatography, Liquid , Circadian Rhythm , Gas Chromatography-Mass Spectrometry , Humans , Male , Middle Aged , Reference Values
9.
Steroids ; 63(2): 80-7, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9516717

ABSTRACT

Dehydroepiandrosterone (DHEA) replacement therapy as compensation for high age-related decline of DHEA and DHEA sulfate production is a matter of intense investigation, since many beneficial effects have been proven, or are suggested and expected. Therefore, DHEA abuse by athletes has been considered by the International Olympic Committee, which banned the substance recently. As DHEA for oral supplementation is easily available, we decided to investigate the effect on the urinary androgen profile of administration along this route of a single substitution dose of 50 mg. Quantitative analysis by gas chromatography-mass spectrometry with selected ion monitoring demonstrated that the drug was readily absorbed with 50 to 75% recovery of dosing after 24 h, and with glucuro- and sulfoconjugates of DHEA, androsterone, and etiocholanolone as the most abundant metabolites. In agreement with reported data found in blood, conversion of exogenous DHEA to the principal biologically active androgen, testosterone, was low but proven to be real by the administration of deuterium-labeled DHEA and the subsequent identification and quantification of deuterium-labeled testosterone. A concentration threshold of 300 micrograms/L of DHEA glucuronide is proposed for the screening of DHEA abuse in sport, but a single replacement dose can only be detected during 8 h. Such a short detection period is the consequence of considerable first-pass hepatic metabolism and also of the high interindividual variability of circulating and urinary DHEA and DHEA sulfate concentrations.


Subject(s)
Androgens/urine , Dehydroepiandrosterone/administration & dosage , Doping in Sports , Gas Chromatography-Mass Spectrometry , Adult , Androsterone/urine , Circadian Rhythm , Dehydroepiandrosterone/pharmacokinetics , Dehydroepiandrosterone Sulfate/urine , Deuterium , Etiocholanolone/urine , Glucuronates/urine , Humans , Kinetics , Male , Testosterone/urine
10.
J Chromatogr B Biomed Appl ; 687(1): 85-91, 1996 Dec 06.
Article in English | MEDLINE | ID: mdl-9001956

ABSTRACT

An analytical screening procedure has been developed for the estimation of total androgen conjugates in post-competition urine, using gas chromatography-mass spectrometry with computerized data acquisition and concentration calculation. Rapid acid-catalyzed methanolysis is a key feature of the method, which allows simultaneous cleavage of glucuronides and sulfates. Analytical data generated by this method for testosterone and epitestosterone are in accordance with our previous results obtained by more accurate isotope dilution mass spectrometry. The usefulness of the ratio of testosterone glucuronide-total epitestosterone as an aid for a better discrimination between physiologically high and pharmacologically high ratios of testosterone glucuronide-epitestosterone glucuronide, which was demonstrated previously, has been confirmed here.


Subject(s)
Androgens/urine , Gas Chromatography-Mass Spectrometry , Glucuronates/urine , Sulfates/urine , Adult , Androgens/chemistry , Doping in Sports , Glucuronates/chemistry , Humans , Male , Substance Abuse Detection , Sulfates/chemistry
11.
Int J Sports Med ; 17(5): 315-9, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8858400

ABSTRACT

There is a potential need for the official criterion of testosterone abuse in sport (the urinary concentration ratio of testosterone glucuronide/epitestosterone glucuronide, TG/EG > 6) to be backed-up by some complementary markers, more particularly in cases of physiologically high TG/EG and when there is suspicion of joint administration of testosterone and epitestosterone. Testosterone, epitestosterone, their glucuro- and sulfoconjugates, 5-androstene-3 beta, 17 alpha-diol glucuronide and 17-hydroxyprogesterone have been analysed by isotope dilution-gas chromatography-mass spectrometry in plasma and urine of seven subjects supplemented with a single oral dose of undecanoates of testosterone and epitestosterone (respectively 40 mg and 1.5 mg). Adequate plasma criteria for testosterone abuse were the ratios of testosterone glucuronide/17-hydroxyprogesterone and testosterone glucuronide/testosterone which increased significantly above basal values for up to 10 h. The same trend was observed for the ratio of urinary glucuronides of testosterone/5-androstene-3 beta, 17 alpha-diol, while TG/EG was not affected by simultaneous administration of epitestosterone. One subject with low basal TG/EG failed to respond to testosterone administration by any significant increase of analysed parameters.


Subject(s)
Epitestosterone/blood , Glucuronates/urine , Substance Abuse Detection/methods , Testosterone/blood , Adult , Chromatography, Gas , Epitestosterone/urine , Glucuronates/blood , Humans , Male , Mass Spectrometry , Middle Aged , Statistics, Nonparametric , Testosterone/urine
12.
J Anal Toxicol ; 19(3): 175-81, 1995.
Article in English | MEDLINE | ID: mdl-7564296

ABSTRACT

A pharmacological dose of a long-acting testosterone ester, testosterone hexahydrobenzoate, was administered intramuscularly to two mares. The time course for some characteristic metabolites in blood and urine was then studied using an analytical method based on gas chromatography-mass spectrometry associated with stable isotope dilution. Among the plasma analytes, testosterone glucuronide was found to be the most adequate indicator for the monitoring of exogenous testosterone up to 2 weeks postadministration if a threshold value of 200 ng/L was applied. In urine, the simultaneous measurement of the concentrations of testosterone sulfate (TS) and epitestosterone sulfate (ES) allowed the calculation of the concentration ratio, TS/ES, which was independent of urine flow and which offered the possibility of detecting testosterone misuse 20 to 30 days after dosing if a tentative threshold value of 8 was adopted. In addition to this ratio, particularly when the TS/ES ratio was close to the cutoff point, it seemed advisable to take into account the concentrations of 5 alpha-androstane-3 beta, 17 alpha-diol (glucuronide) and its 17 beta-isomer (sulfate), which should not exceed 50 micrograms/L.


Subject(s)
Substance-Related Disorders/blood , Substance-Related Disorders/urine , Testosterone , Animals , Drug and Narcotic Control , Female , France , Horses , Injections, Intramuscular , Testosterone/analogs & derivatives , Testosterone/blood , Testosterone/urine
13.
J Endocrinol ; 142(2): 353-60, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7931008

ABSTRACT

Testosterone administration to male athletes can be safely detected in the vast majority of cases by the urinary excretion ratio of testosterone to epitestosterone glucuronides (TG/EG), which may not exceed 6. Some rare cases of physiologically high TG/EG ratios (between 6 and 12) are encountered; these may be attributed to a dysregulation of the testicular secretions of epitestosterone which is decreased, and of epitestosterone sulphate (ES) which is normal or increased. Impaired hydrolysis of circulating epitestosterone sulphate by deficiency of a specific sulphatase acting on 17 alpha-sulphates must also be considered as a possible reason for the decreased availability of epitestosterone for hepatic glucuronidation. Urinary excretions of conjugates and metabolites of testosterone and epitestosterone (expressed in nmol/mmol creatinine) have been determined by gas chromatography-mass spectrometry associated with stable isotope dilution, in a reference population of 90 healthy male subjects and in 12 subjects with chronic TG/EG > 4. Urinary excretion ratios such as TG/(EG+ES), EG/ES and TG/5-androstene-3 beta,17 alpha-diol glucuronide are shown to be efficient criteria which allow discrimination between physiologically high and pharmacologically high TG/EG ratios. A simple oral loading test with deuterium-labelled epitestosterone demonstrates the difference between hepatic and total epitestosterone metabolism clearly, particularly in subjects with physiologically high TG/EG in comparison with subjects with normal TG/EG.


Subject(s)
Epitestosterone/urine , Sports , Substance Abuse Detection , Testosterone/urine , Adolescent , Adult , Deuterium , Epitestosterone/administration & dosage , Epitestosterone/metabolism , Gas Chromatography-Mass Spectrometry , Humans , Indicator Dilution Techniques , Isotope Labeling , Liver/metabolism , Male , Radioimmunoassay , Reference Values , Sensitivity and Specificity , Testosterone/analogs & derivatives
14.
Eur J Endocrinol ; 130(1): 53-9, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8124479

ABSTRACT

In this cross-sectional study on 140 subjects, several testosterone and epitestosterone metabolites have been analyzed by gas chromatography-mass spectrometry associated with stable isotope dilution, a technique requested for doping analysis in general, and detection of exogenous testosterone supply in particular. Urinary excretions of luteinizing hormone, testosterone and epitestosterone glucuronides and sulfates, as well as glucuronides of 5-androstene-3 beta, 17 alpha-diol, 5 alpha- and 5 beta-androstane-3 alpha, 17 alpha-diol and the corresponding 17 beta-isomers, present similar patterns of increase throughout pubertal development, from stage 1 up to stage 5. Excretion levels are significantly different in general between stages 1, 2, 3 and 4, the highest percentage increase being observed between stages 3 and 4. None of the ratios of testosterone to epitestosterone glucuronides are beyond the threshold value of 6, where testosterone abuse by athletes is suspected. No particular pubertal stage exceeded this critical value with a probability higher than p = 0.006, a value that was determined on the whole population. This is consistent with the non-significant differences between correlation slopes of regression curves, relating either testosterone or epitestosterone glucuronide to chronological age. The ratio of testosterone glucuronide to luteinizing hormone increases significantly throughout puberty and this might be a limitation to the widespread use of this ratio for the detection of testosterone misuse.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Epitestosterone/metabolism , Exercise/physiology , Puberty/metabolism , Sports , Testosterone/metabolism , Adolescent , Adult , Androstane-3,17-diol/urine , Androstenediol/urine , Cross-Sectional Studies , Doping in Sports , Epitestosterone/urine , Gas Chromatography-Mass Spectrometry , Humans , Luteinizing Hormone/urine , Male , Reference Values , Regression Analysis , Testosterone/analogs & derivatives , Testosterone/urine
15.
Clin Chem ; 40(1): 106-9, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8287515

ABSTRACT

Combined self-administration of testosterone (T) and epitestosterone (ET) by athletes counteracts the efficiency of the corresponding urinary glucuronides (G) ratio, (T/ET)G, as an indicator of T abuse. I therefore propose 5-androstene-3 beta, 17 alpha-diol (5A3 beta 17 alpha), the immediate metabolic precursor of ET, as a new reference compound for the expression of relative excretions of T and ET. Thus (T/5A3 beta 17 alpha)G and (ET/5A3 beta 17 alpha)G become potential criteria to indicate joint administration of T and ET, since their respective threshold values (2.5 and 1.5) are exceeded even when (T/ET)G remains below the critical value of 6.


Subject(s)
Epitestosterone/urine , Sports , Substance Abuse Detection , Testosterone/urine , Adolescent , Adult , Epitestosterone/administration & dosage , Epitestosterone/pharmacokinetics , False Negative Reactions , Glucuronates/urine , Humans , Male , Reference Values , Self Medication , Testosterone/administration & dosage , Testosterone/pharmacokinetics
17.
Eur J Biochem ; 214(2): 569-76, 1993 Jun 01.
Article in English | MEDLINE | ID: mdl-8513806

ABSTRACT

The ability of human and equine placental microsomes to aromatize 7 alpha-methyl-19-nortestosterone (MNT) was studied. Kinetic analysis indicates that MNT shares the androgen-binding site of human and equine placental microsomal aromatases. Human placental microsomal estrogen synthetase had about a 2.5-fold higher relative affinity for MNT than the equine placental enzyme (KiMNT/Km androstenedione of 32 versus 87). However, MNT was not metabolized by human placental microsomes, whereas it was very actively metabolized by equine placental microsomes. Further studies using purified equine cytochrome P-450arom indicated that the presence of a 7 alpha-methyl group and the absence of a C19 methyl group did not impair its conversion by the purified enzyme. The product of this reaction was separated and identified as 7 alpha-methylestradiol by gas chromatography coupled to mass spectrometry.


Subject(s)
Aromatase/metabolism , Estrenes/metabolism , Nandrolone/analogs & derivatives , Placenta/enzymology , Animals , Aromatase Inhibitors , Binding Sites , Female , Gas Chromatography-Mass Spectrometry , Horses , Humans , In Vitro Techniques , Kinetics , Microsomes/enzymology , Placenta/ultrastructure , Pregnancy
18.
Maturitas ; 16(3): 185-202, 1993 May.
Article in English | MEDLINE | ID: mdl-8515718

ABSTRACT

Doses of 100 mg of micronized progesterone (P) and of 0.5 mg of micronized estradiol (E2) were administered vaginally and orally, respectively, in the early follicular phase of the menstrual cycle in six premenopausal women. In the second cycle, the same doses were administered in the same subjects, orally for P and vaginally for E2. Serial blood samples were collected and the following steroids were assayed by highly reliable techniques: P, E2, estrone (E1), deoxycorticosterone (DOC), 5 alpha- and 5 beta-pregnanolone and the sulfates of E1, E2, and DOC. Circulating P and E2 levels were higher after vaginal than after oral administration, while those of E1 were similar after either route. Metabolites of P (DOC, DOCS and pregnanolone) were higher after oral administration. Concerning estrogen sulfates, E1S concentrations were similar whichever the route, while those of E2S were lower after oral than after vaginal administration. This study has confirmed that metabolism of ingested P and E2 occurs mainly in the intestine. Moreover, P was predominantly metabolized to 5 alpha-reduced derivatives, whatever the route of administration. In view of the metabolic pathways which are operative and of the peripheral plasma levels which were found, the vaginal route appears to be more adequate than the oral one for hormone replacement therapy.


Subject(s)
Estradiol/administration & dosage , Estrogens/blood , Progesterone/administration & dosage , Progesterone/blood , Administration, Intravaginal , Administration, Oral , Adult , Desoxycorticosterone/analogs & derivatives , Desoxycorticosterone/blood , Estradiol/analogs & derivatives , Estradiol/blood , Estrone/analogs & derivatives , Estrone/blood , Female , Humans , Pregnanolone/blood
19.
J Steroid Biochem Mol Biol ; 44(2): 171-7, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8439521

ABSTRACT

Epitestosterone (ET) and testosterone (T), free and sulfoconjugated, as well as 5-androstene-3 beta,17 alpha-diol (5AD3 beta 17 alpha) and its 17 beta-epimer have been analyzed, by gas chromatography-mass spectrometry with stable isotope dilution, in peripheral and spermatic venous plasma of patients with left varicocele. All these androgens are secreted by the testis as evidenced by the significant concentration gradients between peripheral and spermatic venous plasma. Half of the daily ET production is ascribed to the testis, while 95% of T sulfate and roughly 70% of ET sulfate are also of testicular origin. Significant correlations between ET and 5AD3 beta 17 alpha are an indication that the 5-ene pathway is also operative for ET biosynthesis. High ratios of spermatic to peripheral venous plasma levels of ET and 5AD3 beta 17 alpha are also related to the high clearance rates of 17 alpha-hydroxy-androgens.


Subject(s)
Androstenediol/blood , Epitestosterone/metabolism , Testis/metabolism , Adult , Epitestosterone/blood , Gas Chromatography-Mass Spectrometry , Humans , Male , Sulfates/blood , Testosterone/blood , Varicocele/blood
20.
J Steroid Biochem Mol Biol ; 44(2): 179-89, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8439522

ABSTRACT

Doses equivalent to 18, 72 and 216 mg testosterone (T)/week were administered for 6 months to eugonadal men. Urinary excretions of androgen glucuronides (G) were quantitatively analyzed by gas chromatography-mass spectrometry with stable isotope dilution during periods of control (without hormone treatment), T administration and recovery. The lowest dosage T administration did not affect the androgen profile, while higher dosages generally increased urinary excretions of T metabolites (TG, T sulfate, glucuronides of androsterone, etiocholanolone, 5 alpha- and 5 beta-androstane-3 alpha,17 beta-diol) and decreased excretions of conjugates of epitestosterone (ET) and its precursor androgen 5-androstene-3 beta,17 alpha-diol. A dose-dependent decrease of urinary LH in response to T was also observed. The ratio (T/ET)G, which is the sole official criterium for assessment of T self-administration by athletes, increased above the threshold value of 6 in most of the subjects, but not all, after the two highest dosage T regimens, and returned to normal during the recovery period. False positive or negative testing emphasizes the need for improvement of testing procedures. In this regard, valuable complementary information may be gained from ratios such as TG/ET(Total), TG/LH, (T/5-androstene-3 beta,17 alpha-diol)G, (5 alpha/5 beta)androstane-3 alpha,17 alpha-diol and (5 alpha/5 beta)androstane-3 alpha,17 beta-diol.


Subject(s)
Androgens/urine , Doping in Sports , Substance Abuse Detection , Testosterone/analogs & derivatives , Testosterone/urine , Adult , Humans , Male , Reference Values , Reproducibility of Results , Testosterone/administration & dosage , Testosterone/pharmacology
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