Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042755 (masculinization)
 2,562 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Androgen insensitivity was demonstrated in two male siblings with partial masculinization of the external genitalia. They had a previously undescribed defect characterized postpubertally by high plasma testosterone and luteinizing hormone concentrations with low serum follicle-stimulating hormone levels. Studies in skin fibroblasts showed normal androgen receptor affinity and capacity for 5alpha-dihydrotestosterone (DHT), normal nuclear retention of the receptor-DHT complex, and normal conversion of testosterone to DHT.
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PMID:Male pseudohermaphroditism with partial androgen insensitivity. 83 6

Androgen resistance can be divided into two broad categories: deficiency in 5 alpha-reductase and defects in the androgen receptor. Studies of these two disorders have provided insight into both the normal pathway of androgen action and into the pathogenesis of abnormal sexual development. 5 alpha-Reductase deficiency is a rare autosomal recessive disorder involving the 5 alpha-reductase 2 enzyme; affected males exhibit a defect in virilization most evident as impairment of the virilization of the external genitalia and urogenital sinus. Disorders of the androgen receptor in genetic males cause a spectrum of developmental abnormalities that vary from phenotypic females to men with mild defects in virilization. On functional grounds we have divided these defects into absence of receptor function, qualitatively abnormal receptors, quantitative defects in receptor amount, and apparently normal receptor. Cloning of the cDNA for the receptor and application of the polymerase chain reaction techniques for sequencing of mutants made it possible to analyze these defects at the molecular level. It is now apparent that the functional categorization underestimated the complexity of the mutations. Indeed, major gene deletions and/or rearrangements, single amino acid substitutions, and premature termination codons all can cause variably severe functional abnormalities.
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PMID:Syndromes of androgen resistance. 153 91

The number of muscle fibers in the vocal organ of the adult male African clawed frog, Xenopus laevis, exceeds that of adult females. This sex difference is the result of rapid fiber addition in males between the end of metamorphosis, post-metamorphic stage 0 (PM0) and PM2. At PM0, male and female frogs have similar numbers of laryngeal muscle fibers. Males then add more muscle fibers than females and achieve an adult value that is 1.7 times the female number. Males castrated at PM0 have the same fiber number as females. Ovariectomy at PM0 does not alter muscle fiber addition in females. Gonadectomy at PM2 has no effect on fiber addition in either sex. Females attain masculine muscle fiber number if their ovaries are replaced with a testis at metamorphosis. Exogenous testosterone treatment at PM0 significantly increases fiber number in females but not in males. Exogenous testosterone given at PM2 has no effect on fiber number in females but decreases fiber number in males. We conclude that the testes are necessary for the marked addition of laryngeal muscle fibers seen in male X. laevis between PM0 and PM2. The masculine pattern of muscle fiber addition can be induced in females provided with a testis. Androgen secretion from the testes most probably accounts for masculinization of laryngeal muscle fiber number. After PM2, androgens are no longer necessary for muscle fiber addition and cannot increase fiber number in females.
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PMID:Hormone-sensitive stages in the sexual differentiation of laryngeal muscle fiber number in Xenopus laevis. 208 15

A familial form of incomplete androgen insensitivity syndrome (AIS) is reported. The index case was first seen at 9 months of age for ambiguous genitalia. Diagnosis of AIS, suspected but first discarded on the basis of an androgen sensitivity test, was finally made at puberty on the discordance between poor virilization and elevated levels of both testosterone and LH, a florid gynecomastia, and the exclusion of any enzymatic defect in testosterone biosynthesis of 5 alpha-reductase deficiency. Androgen receptors in public skin were within the limits of normal for total number, with normal affinity. Familial occurrence included 2 first cousins born 7 and 10 years later, a maternal grand-uncle with similar ambiguous genitalia, and a maternal uncle with the gynecomastia-preserved fertility syndrome. This case report illustrates the heterogeneity of AIS in a given family and the difficulty of and early positive diagnosis in a newborn presenting with sexual ambiguity.
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PMID:[Incomplete androgen insensitivity syndrome. Difficulties of diagnosis and management]. 232 64

The traditional options available for the correction of hemodialysis-related anemia are blood transfusions and androgen therapy to stimulate erythropoiesis. A new therapeutic option, recombinant human erythropoietin (r-HuEPO; EPOGEN, AMGEN Inc, Thousand Oaks, CA), is currently undergoing clinical trials. Each treatment alternative has certain attendant adverse effects. The adverse effects of transfusion include transmission of infections such as hepatitis or acquired immunodeficiency syndrome, iron overload, and sensitization to histocompatibility antigens. Androgen therapy can cause masculinization of women and children and, in some forms, is associated with a high incidence of abnormal liver function. Treatment with r-HuEPO has some potential adverse effects, including hypertension, thrombosis of arteriovenous fistulae, prolonged duration of dialysis, hyperkalemia, and iron deficiency. Gradual and careful introduction of r-HuEPO should prevent hypertension from becoming problematic.
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PMID:Adverse effects of therapy for the correction of anemia in hemodialysis patients. 264 19

Male pseudohermaphroditism due to 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) deficiency has a high prevalence within the Arab population of the Gaza strip and is characterised by marked virilization at puberty, leading in many cases to the spontaneous adoption of a male gender role. As a result of this, parents of 7 affected male infants (aged 1-10 months) born with female phenotype requested early gender reassignment. Diagnosis was suspected in 5 on the basis of a positive family history, but confirmed in all cases by the finding of low to normal testosterone levels (30-184 ng/dl) with high delta 4-androstenedione levels (188-808 ng/dl), after hCG. Treatment with im testosterone oenanthate (25-50 mg/dose) was given in one to three 3-months courses and penile size was increased into the normal range without evoking a significant increase in height velocity or skeletal maturation. Five patients underwent the first stage of male genitoplasty between 2 and 3 years of age. This consisted of bilateral orchidopexy, chordee release and penile lengthening - yielding finally an anatomically normal-sized and shaped penis. Androgen responsive male pseudohermaphroditism due to 17 beta-HSD deficiency or a similar defect and diagnosed in infancy should be treated as soon as possible with systemic testosterone before considering any sex change, and in preparation for male genitoplasty. Early gender reassignment according to genetic and gonadal sex is probably the management of choice for these cases since this may result in a normal adjustment to the male gender role, particularly after puberty.
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PMID:Male pseudohermaphroditism due to 17 beta-hydroxysteroid dehydrogenase deficiency: gender reassignment in early infancy. 301 38

We examined effects of exogenous androgen (testosterone and dihydrotestosterone) on vocalizations of ovariectomized, adult female South African clawed frogs, Xenopus laevis. When paired with sexually active males, all ovariectomized females exhibited ticking, the unreceptive or 'release' call. Ticking consists of low amplitude, regularly spaced clicks with a mean interclick interval of 154 ms. When androgen-treated and paired with sexually active males, these ovariectomized females also exhibited an aberrant call (atypical ticking) in which click multiples replaced the single clicks of ticking. Mean ICI's for atypical ticking were 37 ms for click doublets and 22 ms for click quadruplets. Androgen treatment decreased the total time spent vocalizing (typical and atypical ticking) by ovariectomized females. All androgen-treated females were then tested repeatedly with sexually receptive females in an attempt to elicit the male-typical vocalization, mate calling. Six of 17 females did not vocalize at all, even when gonadotropin injected. Eight females gave rapid (mean ICI, 36 ms) trains of clicks in an irregular temporal pattern (tick-like calls). Three females gave brief trills with alternating fast and slow components. Comparison of mate call-like vocalizations of androgen-treated females to mate calling of males reveals that calls in females are considerably shorter in duration (female: 0.32 min versus male: 45 min) and slower in tempo (ICI's; fast trill, female: 21 ms, male: 14 ms; slow trill, female: 36 ms, male: 28 ms). Incomplete masculinization of the vocal pattern of females by androgen treatment in adulthood may be due to developmental constraints on the modifiability of the neurons and muscles responsible for calling.
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PMID:Androgen-induced alterations in vocalizations of female Xenopus laevis: modifiability and constraints. 352 87

The authors administered to six transsexual women at three-month intervals androgenic depot preparations: testosterone undecanoate (Andriol-Organon) by the oral route and testosterone isobutyrate (Agovirin depot-Spofa) in injections. The achieved changes were evaluated by clinical and laboratory examinations, i.e. somatic changes as well as changes of hormonal indicators in plasma, urine and saliva, changes in the TeBG binding capacity, the effect of the administered hormones on liver functions, glucose metabolism and secretory insulin response. The high plasma androgen level did not vary substantially. After Andriol administration, a significant decrease of plasma TeBG was achieved, and an increase of the free testosterone fraction in saliva which was retained three months after discontinuation of the treatment. Both preparations caused the required virilization, whereby the action of Agovirin depot-Spofa in the selected dose was, as regards the speed of onset and intensity of the androgenization symptoms, more effective. The gonadotropin levels were not changed significantly during short-term administration. No interference with liver functions and glucose metabolism was observed. The patients tolerated both preparations well.
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PMID:Androgen administration to transsexual women. II. Hormonal changes. 355 12

Female squirrels were injected at birth with 50 or 1000 micrograms testosterone propionate (TP); control males and females were treated with oil vehicle. Squirrels were gonadectomized at 47 days of age. Body mass was recorded weekly and plasma luteinizing hormone (LH) was determined once monthly over the next year. Marked annual cycles in body mass were manifested by 30 out of 31 squirrels. Peak body mass and peak-to-trough differences were greater for control male and TP-female squirrels than for control female squirrels. Trough body weights did not differ among the groups. Luteinizing hormone was detectable in all male and most androgenized females but not in any control female squirrels during the first 4 mo after gonadectomy. Peak LH values were significantly greater for control male than for control female squirrels and were not influenced by neonatal androgenization in females. Testosterone propionate treatment also did not affect sex differences in timing of LH peaks or the total number of months in which LH was detectable. We conclude that testicular hormones secreted during the early postnatal period induce sex differences in the circannual pattern of weight change and some aspects of LH secretion. Complete masculinization, however, either requires more extensive action of gonadal hormones, perhaps both pre- and postnatally, or occurs through some androgen-independent mechanism.
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PMID:Neonatal androgenization in ground squirrels: influence on sex differences in body mass and luteinizing hormone levels. 369 66

Androgens and estrogens have been implicated in the activation of a variety of sexually-dimorphic, hormone-dependent behaviors in the adult zebra finch. In the present report, several biochemical characteristics of two putative sex steroid receptors, androgen- and estrogen-binding activities, were determined by DNA-cellulose chromatography in brain tissues from these birds. High-affinity, limited-capacity receptors for androgens and estrogens were found in cytosolic extracts of telencephalon, diencephalon-mesencephalon, and metencephalon-myelencephalon from adult male and female zebra finches. Androgen-binding activity reproducibly adhered to DNA-cellulose and was eluted within the 110-150 mM NaCl region of a linear salt concentration gradient. Estrogen receptors adhered to DNA-cellulose and exhibited elution maxima between 170 mM and 210 mM NaCl. Collectively these data indicate that brain regions of zebra finches contain steroid receptors that are similar to those found in the brains of other vertebrates and that their biochemical properties are similar in males and females. Quantitatively, males consistently exhibited higher androgen binding than females in both anterior and posterior telencephalic areas. Females treated with estradiol immediately after hatching exhibited adult levels of androgen binding corresponding to those detected in males. Masculinization of the androgen receptor system by early steroid exposure is discussed.
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PMID:Androgen and estrogen receptors in adult zebra finch brain. 379 93


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