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Rapid Communications in Mass... 2003The in vivo phase I biotransformation of 17 alpha-methyltestosterone in the horse leads to the formation of a complex mixture of regio- and stereoisomeric C(20)O(2),...
In vivo biotransformation of 17 alpha-methyltestosterone in the horse revisited: identification of 17-hydroxymethyl metabolites in equine urine by capillary gas chromatography/mass spectrometry.
The in vivo phase I biotransformation of 17 alpha-methyltestosterone in the horse leads to the formation of a complex mixture of regio- and stereoisomeric C(20)O(2), C(20)O(3) and C(20)O(4) metabolites, excreted in urine as glucuronide and sulphate phase II conjugates. The major pathways of in vivo metabolism are the reduction of the A-ring (di- and tetrahydro), epimerisation at C-17 and oxidations mainly at C-6 and C-16. Some phase I metabolites have been identified previously by positive ion electron ionisation capillary gas chromatography/mass spectrometry (GC/EI + MS) mainly from the characteristic fragmentation patterns of their methyloxime-trimethylsilyl ether (MO-TMS), enol-TMS or TMS ether derivatives. Following oral administration of 17 alpha-methyltestosterone to two castrated thoroughbred male horses, the glucuronic acid conjugates excreted in post-administration urine samples were selectively hydrolysed by E. coli beta-glucuronidase enzymes. Unconjugated metabolites and the steroid aglycones obtained after enzymatic deconjugation were isolated from urine by solid-phase extraction, derivatised as MO-TMS ethers and analysed by GC/EI + MS. In addition to some of the known metabolites previously identified from the characteristic mass spectral fragmentation patterns of 17 alpha-methyl steroids, some isobaric compounds exhibiting a diagnostic loss of 103 mass units from the molecular ions with subsequent losses of trimethylsilanol or methoxy groups and an absence of the classical D-ring fragment ion were detected. From an interpretation of their mass spectra, these compounds were identified as 17-hydroxymethyl metabolites, formed in vivo in the horse by oxidation of the 17-methyl moiety of 17 alpha-methyltestosterone. This study reports on the GC/EI + MS identification of these novel 17-hydroxymethyl C(20)O(3) and C(20)O(4) metabolites of 17 alpha-methyltestosterone excreted in thoroughbred horse urine.
Topics: Animals; Biotransformation; Gas Chromatography-Mass Spectrometry; Horses; Male; Methyltestosterone; Molecular Structure
PubMed: 12569442
DOI: 10.1002/rcm.909 -
Fertility and Sterility Jun 1978Twenty-four women with documented endometriosis externa were treated with methyltestosterone. Twenty-one of these patients desired fertility and three conceived (one...
Twenty-four women with documented endometriosis externa were treated with methyltestosterone. Twenty-one of these patients desired fertility and three conceived (one after methyltestosterone therapy alone, two after conservative operation followed by methyltestosterone treatment). Ten patients later required surgical therapy for recurrence of pain, although all but one patient had initial relief of pain (3 to 6 months after therapy). These results of therapy are contrasted to those of similar studies in the literature in which methyltestosterone and other agents were used.
Topics: Adult; Endometriosis; Female; Humans; Infertility, Female; Methyltestosterone; Pregnancy; Pregnancy Complications; Retrospective Studies
PubMed: 658477
DOI: 10.1016/s0015-0282(16)43339-x -
The American Journal of Dermatopathology Dec 2012
Topics: Estrogens, Esterified (USP); Female; Humans; Methyltestosterone; Middle Aged; Telangiectasis
PubMed: 22008716
DOI: 10.1097/DAD.0b013e31820ee697 -
Animal Reproduction Science Dec 2016Commercial culture of Brook trout (Salvelinus fontinalis) in Tasmania was partly abandoned due to sexual maturation of male fish early on during the estuarine rearing...
Commercial culture of Brook trout (Salvelinus fontinalis) in Tasmania was partly abandoned due to sexual maturation of male fish early on during the estuarine rearing phase. Maturation adversely affects body mass, flesh quality and immunocompetency effectively. Sex reversal techniques such as the in-feed addition of a synthetic androgen have proven difficult to adapt in brook trout. An appropriate timing, duration and delivery vehicle for administration of 17α-methyltestosterone (MT) to produce phenotypic males (neomales) from genotypically female brook trout required further investigation. In this study, groups of brook trout eggs (n=1000) maintained at 9.5±0.15-10±0.14°C, were immersed in MT (400μgL) for four hours on two alternate days (two immersions/group) staggered over a two week period surrounding the hatch of embryos (control groups excluded). The groups were then split and half received MT-supplemented feed for 60days and the other a standard diet. Following an 11 month on-growing period sex phenotypes were determined by gross & histological gonad morphology. The highest proportion of male phenotypes (75%) was found in fish immersed six and four days pre-hatch and subsequently fed a normal diet. Fish fed a MT supplemented diet and immersed in MT showed significantly higher proportions of sterile fish. These data indicate that a pre-hatch immersion-only regime (4-6days pre-hatch at 9.5°C) should be pursued as a target for optimization studies to further refine the effective concentration and duration of exposure to MT for the successful production of neo-male brook trout.
Topics: Animal Feed; Animals; Disorders of Sex Development; Drug Administration Schedule; Female; Gonads; Male; Methyltestosterone; Sex Determination Analysis; Time Factors; Trout
PubMed: 27802873
DOI: 10.1016/j.anireprosci.2016.10.008 -
General and Comparative Endocrinology Sep 2013Pengze crucian carp (Carassius auratus var. pengze, Pcc), a triploid gynogenetic fish, was used in this study to investigate the cross-talk between EDCs and steroid...
Molecular characterization of five steroid receptors from pengze crucian carp and their expression profiles of juveniles in response to 17α-ethinylestradiol and 17α-methyltestosterone.
Pengze crucian carp (Carassius auratus var. pengze, Pcc), a triploid gynogenetic fish, was used in this study to investigate the cross-talk between EDCs and steroid receptors. The full-length cDNAs of five steroid receptors (esr1, er alpha2, esr2a, esr2b, ar) and partial cDNA of vtg B were isolated. The tissue distributions of these genes were analyzed in adult fish by qRT-PCR. Then the expression profiles of five steroid receptors (esrs and ar) and vtg B were detected in the juveniles exposed to 17α-ethinylestradiol (EE2, 0.1, 1 and 10ng/L) and 17α-methyltestosterone (MT, 50μg/L) for 4weeks. The results demonstrated that esrs, ar, and vtg B were predominantly expressed in liver of adult fish. However, among these detected genes, esr1 and er alpha2 mRNAs are sensitive biomarkers in response to EE2 at 0.1, 1, and 10ng/L for 1 and 2weeks compared to esr2a, esr2b, ar, and vtg B in the juveniles of mono-female gynogenetic fish. Totally, the subtypes of esrs show biphasic responses to EE2 exposures for 4weeks, and most of the EE2 exposures at 0.1, 1, and 10ng/L for 1, 2, 3 and 4weeks did not induce the mRNA expressions of vtg B. However, 1-, 2-, and 4-week 50μg/L MT all significantly stimulated vtg B transcripts. Further investigations are needed to elucidate the mechanism underlying the insensitivity or down-regulation of vtg B mRNA in response to EE2 in juvenile Pcc.
Topics: Animals; Carps; Ethinyl Estradiol; Female; Male; Methyltestosterone; Receptors, Steroid; Reverse Transcriptase Polymerase Chain Reaction
PubMed: 23806426
DOI: 10.1016/j.ygcen.2013.06.011 -
Current Opinion in Investigational... Nov 2002Cellegy is developing a drug delivery system designed to facilitate the transdermal and topical delivery of testosterone for the potential treatment of male hypogonadism... (Review)
Review
Cellegy is developing a drug delivery system designed to facilitate the transdermal and topical delivery of testosterone for the potential treatment of male hypogonadism (as Tostrex) and decreased sexual energy in post-menopausal women (asTostrelle) [218118], [314726], [351823]. Following phase III dinical trials of Tostrex for male hypogonadism, initiated in March 2000 [361133], an NDA submission for male hypogonadism was filed in June 2002, after a pre-NDA meeting with the FDA late in 2001 [453374]. By March 2002, phase II/III clinical studies in postmenopausal women were underway in the US [444857].
Topics: Administration, Cutaneous; Animals; Clinical Trials as Topic; Gels; Humans; Methyltestosterone; Sexual Dysfunction, Physiological; Technology, Pharmaceutical
PubMed: 12476964
DOI: No ID Found -
Fertility and Sterility Jan 1976Sixty-four patients who had infertility associated only with endometriosis were treated with methyltestosterone, 5 mg/day, continuously for a period of 6 months. The...
Sixty-four patients who had infertility associated only with endometriosis were treated with methyltestosterone, 5 mg/day, continuously for a period of 6 months. The patients continued to ovulate while receiving medication and 12 patients became pregnant, on an average, 6 months after the initiation of therapy. A computer analysis indicated that approximately 30% of the patients could expect pregnancy within 2 years after the testosterone treatment was begun. The side effects of the low-dose methyltestosterone therapy were acne in 6% of the patients, mild hirsutism in 3%, and an occasional delay in ovulation.
Topics: Adult; Endometriosis; Female; Humans; Infertility, Female; Methyltestosterone; Pelvic Neoplasms; Pregnancy
PubMed: 1245246
DOI: 10.1016/s0015-0282(16)41598-0 -
Journal of Chromatography Mar 1985A method for the quantitative estimation of methyltestosterone and methyltestosterone-d3 in biological fluids has been developed using gas chromatography-mass...
A method for the quantitative estimation of methyltestosterone and methyltestosterone-d3 in biological fluids has been developed using gas chromatography-mass spectrometry-selected-ion monitoring. Methyltestosterone-d6 was used as an internal standard. Methyltestosterone and methyltestosterone-d3 in serum were determined based on the peak height ratios of the molecular ions of methyltestosterone, methyltestosterone-d3 and methyltestosterone-d6. Sensitivity, specificity, precision, accuracy and reproducibility of the present method were demonstrated to be satisfactory for application to pharmacokinetic and bioavailability studies.
Topics: Biological Availability; Gas Chromatography-Mass Spectrometry; Humans; Kinetics; Methyltestosterone
PubMed: 3998019
DOI: 10.1016/0378-4347(85)80099-2 -
Homeopathy : the Journal of the Faculty... Jul 2012Nile tilapia (Oreochromis niloticus), are widely used in fish farming, hormonal treatments are used to increase productivity. Studies of the characteristics of the fiber...
BACKGROUND
Nile tilapia (Oreochromis niloticus), are widely used in fish farming, hormonal treatments are used to increase productivity. Studies of the characteristics of the fiber types are important in species that have well developed muscle mass, such as Nile tilapia.
METHODS
A total of 4800 post-larval fish were randomly assigned by tank to receive one of three treatments: Control (30°GL alcohol), Homeopathic complex (Homeopatila RS) or Hormone (17-α-methyltestosterone) supplemented in the feed for 28 days. Survival and morphological parameters were measured at day 45.
RESULTS
At day 45, the survival rates were 54.1% (Control), 87.8% (Homeopathy), 50.3% (Hormone). The mean final weight for Homeopathy was statistically significantly lower (1.07 g) than the other two groups: Control (1.81 g) and Hormone (2.04 g). Mean total lengths were Control (4.75 cm), Hormone (4.49 cm), statistically significantly different from Homeopathy (3.83 cm). Average partial length, trunk length, height and body width were significantly lower for Homeopathy than Control or Hormone (p<0.05) Homeopathy treated fish had significantly greater muscle fiber diameter than the other two groups.
CONCLUSIONS
Fish treated with the homeopathic complex had improved survival and muscle fiber hypertrophy, but were smaller (probably related to increased survival and overcrowding) compared to fingerlings treated with synthetic hormone or control.
Topics: Animals; Cichlids; Homeopathy; Methyltestosterone; Muscle Fibers, Fast-Twitch
PubMed: 22818232
DOI: 10.1016/j.homp.2012.05.005 -
JAMA Apr 1968
Topics: Bile Ducts, Intrahepatic; Female; Humans; Liver Cirrhosis, Biliary; Methyltestosterone; Middle Aged
PubMed: 5694548
DOI: No ID Found