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Testosterone

About: Testosterone is a research topic. Over the lifetime, 23258 publications have been published within this topic receiving 808079 citations. The topic is also known as: 4-androsten-17beta-ol-3-one & 4-Androsten-3-one-17b-ol.


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Journal ArticleDOI
TL;DR: A striking increase of both testosterone and androstenedione levels was noted after administration of testosterone undecanoate, which is otherwise only achieved by parenteral testosterone application, and promises to be an effective medication for oral androgen replacement.
Abstract: Plasma testosterone and androstenedione levels in men were measured after oral administration of free testosterone and testosterone undecanoate. Both androgens were determined by simultaneous, specific radioimmunoassays after separation and isolation by thin layer chromatography. While free unesterified testosterone had no effect on plasma androgen levels, a striking increase of both testosterone and androstenedione levels was noted after administration of testosterone undecanoate, which is otherwise only achieved by parenteral testosterone application. This effect of testosterone undecanoate is probably due to absorption via the lymph rather than via the portal vessels so that peripheral circulation is reached before metabolism in the liver. Testosterone undecanoate promises to be an effective medication for oral androgen replacement.

162 citations

Journal ArticleDOI
TL;DR: All subjects with PAIS maintained at postpubertal age the gender identity and social sex that was assigned to them in infancy, in contrast to other forms of pseudohermaphroditism.
Abstract: Androgen insensitivity syndrome (AIS) is caused by mutations in the androgen receptor gene and is associated with a variety of phenotypes in 46,XY individuals, ranging from phenotypic women [complete form (CAIS)] to men with minor degrees of undervirilization or infertility [partial form (PAIS)]. We studied 32 subjects with male pseudohermaphroditism from 20 families (9 CAIS, 11 PAIS) with the following criteria for AIS: 46,XY karyotype, normal male basal and human chorionic gonadotropin-stimulated levels of serum testosterone and steroid precursors, gynecomastia at puberty, and, in prepubertal patients, a family history suggestive of X-linked inheritance. The entire coding region of the androgen receptor gene was analyzed, and mutations were found in all families with CAIS and in eight of 11 families with PAIS. Fifteen different mutations were identified, including five (S119X, T602P, L768V, I898F, and P904V) that have not been described previously. Detailed clinical and hormonal features were compared with genotype in 25 subjects with AIS and confirmed by mutational analysis. LH hormone levels and the LH x testosterone product were high in all postpubertal subjects with AIS. All subjects with PAIS maintained at postpubertal age the gender identity and social sex that was assigned to them in infancy, in contrast to other forms of pseudohermaphroditism.

162 citations

Journal ArticleDOI
TL;DR: It is suggested that the sexual dysfunction associated with radical prostatectomy cannot be explained by androgen deficiency alone and that the normal prostate and/or prostate neoplasm could secrete a substance or substances that give negative feedback control to pituitary gonadotropin secretion.

162 citations

Journal ArticleDOI
TL;DR: The data indicate that spermatogenesis may be abnormal after orchipexy, and suggest that men with unilaterally undescended testis may have bilateral testicular abnormality.
Abstract: Testicular function was determined in 29 men, 21 to 35 years old, who had undergone orchiopexy for unilaterally undescended testis at four to 12 years of age. Serum testosterone and dialyzable testosterone concentrations of these men were not significantly different from those of a control group of 30 normal men, and their basal serum luteinizing hormone concentrations and serum luteinizing hormone responses to synthetic gonadotropin-releasing hormone were only slightly higher than those of the normal men. The mean sperm density of the patients, however, was only one third of that of the normal men (P<0.001). The mean serum follicle stimulating hormone response to gonadotropin-releasing hormone of the patients was double that of the normal men (P<0.001). The data indicate that spermatogenesis may be abnormal after orchiopexy, and suggest that men with unilaterally undescended testis may have bilateral testicular abnormality. (N Engl J Med 295:15–18, 1976)

162 citations

Journal ArticleDOI
TL;DR: The relative importance of AR and ER activation has been studied in pubertal male AR knockout and WT mice after orchidectomy and androgen replacement therapy, either with or without an aromatase inhibitor.
Abstract: The relative importance of AR and ER activation has been studied in pubertal male AR knockout and WT mice after orchidectomy and androgen replacement therapy, either with or without an aromatase inhibitor. AR activation dominates normal trabecular bone development and cortical bone modeling in male mice. Moreover, optimal periosteal bone expansion is only observed in the presence of both AR and ER activation. Introduction: Androgen receptor (AR)–mediated androgen action has traditionally been considered a key determinant of male skeletal growth. Increasing evidence, however, suggests that estrogens are also essential for normal male bone growth. Therefore, the relative importance of AR-mediated and estrogen receptor (ER)–mediated androgen action after aromatization remains to be clarified. Materials and Methods: Trabecular and cortical bone was studied in intact or orchidectomized pubertal AR knockout (ARKO) and male wildtype (WT) mice, with or without replacement therapy (3–8 weeks of age). Nonaromatizable (dihydrotestosterone [DHT]) and aromatizable (testosterone [T]) androgens and T plus an aromatase inhibitor (anastrazole) were administered to orchidectomized ARKO and WT mice. Trabecular and cortical bone modeling were evaluated by static and dynamic histomorphometry, respectively. Results: AR inactivation or orchidectomy induced a similar degree of trabecular bone loss (−68% and −71%, respectively). Both DHT and T prevented orchidectomy-induced bone loss in WT mice but not in ARKO mice. Administration of an aromatase inhibitor did not affect T action on trabecular bone. AR inactivation and orchidectomy had similar negative effects on cortical thickness (−13% and −8%, respectively) and periosteal bone formation (−50% and −26%, respectively). In orchidectomized WT mice, both DHT and T were found to stimulate periosteal bone formation and, as a result, to increase cortical thickness. In contrast, the periosteum of ARKO mice remained unresponsive to either DHT or T. Interestingly, administration of an aromatase inhibitor partly reduced T action on periosteal bone formation in orchidectomized WT mice (−34% versus orchidectomized WT mice on T), but not in ARKO mice. This effect was associated with a significant decrease in serum IGF-I (−21% versus orchidectomized WT mice on T). Conclusions: These findings suggest a major role for AR activation in normal development of trabecular bone and periosteal bone growth in male mice. Moreover, optimal stimulation of periosteal growth is only obtained in the presence of both AR and ER activation.

162 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20224
2021509
2020435
2019438
2018456
2017505