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The Birch reduction of 3-methoxy-B-nor-8-isoestra-1,3,5(10)-trienes followed by acid hydrolysis produces steroid androgen 19,B-dinor-8,10-iso-analogues. By means of X-ray analysis and correlation NMR spectroscopy of 16,16-dimethyl-D-homo-19,B-dinor-8-isotestosterone, C(20)H(30)O(2), it is demonstrated that the main conformations in the crystal and in solution for two 19,B-dinor-8,10-iso-analogues are, in general, the same.
The costovertebral organs [CVO] and seminel vesicles [SV] of the hamster exhibit high saturable androgen uptake. The physicochemcal characteristics of the cytoplasmic androgen receptor present in these tissues have been determined and compared to those obtained in rat prostate[P]. Using the synthetic androgen R 1881 [methyltrienolone] as a radioactive ligand, it has been shown that the affinity of this compound for the cytosol CVO receptor [Kd = 0.7 +/- 0.1 nM] is similar to that for the crytosol SV receptor [Kd = 2.4 +/- 0.9 nm] in hamsters and the cytosol P receptor [Kd = 0.6 +/- 0.1 nM] in rats. The hormonal specificity of binding in these tissues is restricted to androgens. Moreover, testosterone and dihydrotestosterone have the same relative binding affinity in CVO and SV compared to R 1881. Following castration, the total number of androgen sites, as measured by an exchange assay with R 1881, decreases rapidly and parallels with a fall in lipogenic activity. Administration of an androgen rapidly restores binding capacity.
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The effect on serum PRL levels of lowering serum oestradiol (E2) concentration by short-term administration of an aromatase activity inhibitor, hydrotestolactone (HT), was studied in six healthy male subjects. After HT administration serum E2 levels decreased from 68 +/- 5.8 to 26 +/- 2.5 pmol/l (mean +/- SE, P less than 0.05). These E2 changes were accompanied by a significant decrease in mean 2-h PRL levels from 11.2 +/- 2.1 to 6.5 +/- 1.6 ng/ml mean +/- SE, P less than 0.05). The evaluation of individual percentage change from basal concentrations showed a varying decrease in all subjects. These findings suggest that under physiological conditions E2 may be one of the factors which control blood PRL concentrations in men.
OBJECTIVE: To measure the effect of androgens or aromatase activity as an index of androgen responsiveness in patients with androgen insensitivity. DESIGN: Genital skin fibroblasts were established in culture using primary skin explants obtained from normal males at the time of circumcision and from androgen insensitive patients who had surgery either for gonadectomy (complete androgen insensitivity syndrome) or for reconstruction of the external genitalia (partial androgen insensitivity syndrome). PATIENTS: Foreskin samples were obtained at the time of circumcision in 27 normal males. Scrotal or labia majora skin was obtained at the time of surgery from 14 patients with the complete and 22 with the partial forms of the androgen insensitivity syndrome. MEASUREMENTS: Basal and stimulated levels of aromatase activity were measured in genital skin fibroblasts following preincubation with natural and synthetic, nonmetabolizable androgens. RESULTS: Following a 48-hour preincubation with testosterone or dihydrotestosterone, there was a five to six-fold stimulation of aromatase activity in normal fibroblasts. Mibolerone, a synthetic androgen, produced similar results. The stimulatory effect was blocked by anti-androgens. Seven patients with partial androgen insensitivity, of whom four were either receptor deficient or showed a qualitative defect in androgen binding, had reduced mibolerone induced stimulation of aromatase activity. All ten patients with receptor negative complete androgen insensitivity had an absent response. There was no aromatase induction in a further three patients with complete androgen insensitivity who were receptor positive. Two siblings in the latter group had an exon deletion encoding for part of the DNA binding domain of the androgen receptor. CONCLUSIONS: Androgens stimulate aromatase activity in genital skin fibroblasts from normals. The response is mediated via the androgen receptor and can be decreased or absent in patients with the androgen insensitivity syndrome. This may be a useful in-vitro marker of androgen responsiveness in such patients.
A review of pharmacological therapy in male infertility shows that apart from specific therapy with gonadotropins in hypogonadotropic hypogonadism, treatment in normogonadotropic idiopathic oligozoospermia and asthenozoospermia is still empirical and often unsuccessful. Modern therapy is based on three pharmacological groups of compounds: gonadotropins, androgens and kininogenases, the latter releasing pharmacologic active kinin peptides from kininogen. In addition, antiestrogens and gonadotropin-releasing hormones seem to be promising agents for the near future. The use of antibiotics is of great importance in the therapy of male genital tract infections which often to a reduced fertility. Several other drugs (amino acids, psychopharmaceuticals, spasmolytic agents, trijodothyronine, glucocorticoids, vitamins) seem to be suitable in individuals cases, but in greater group of patients these agents do not improve fertility. Using the mentioned hormonal and nonhormonal pharmacological agents considerable progress can be demonstrated in the therapy of male infertility. However, before initiating any therapy it is important to exclude patients whose cause of infertility is untreatable or those who require surgery. Finally, it is hoped that additional progress in treatment of male infertility will soon be made possible by further improvement of fundamental research in andrology. Especially important is the development of better criteria for selection of patients for any form of therapy in order to make more specific and less empirical approaches for treatment of male infertility available.
A pregnant bitch was treated with a synthetic testosterone mixture on approximately day 40. The female offspring (six pups) showed an increased anogenital distance, vaginal enlargement and a variable amount of vaginal discharge. The urinary orifice was found dorsally in the vestibulum, stooled on a protruding phallus-like structure. All six pups underwent a laparotomy and subsequent spaying and a modified ventral episioplasty technique to lift up the labia to a more vertical position in order to prevent urine accumulation. Histopathological examination of the genital tracts demonstrated the presence of bilateral ovotestis and remnants of the Wolffian duct system in all cases. The finding of true hermaphroditism of the offspring after exogenous androgen administration during gestation of the bitch has not yet been reported elsewhere.
The suitability of an exchange assay with methyltrienolone (R1881) for the measurement of androgen receptors in human prostatic tumours has been investigated. Having established the specificity of this compound for androgen receptor assay, a pilot study was carried out to measure dihydrotestosterone (DHT) receptor in 27 cases of benign hypertrophy and 18 cases of malignant tumour of the prostate.
Non-prescribed use of anabolic androgenic steroids (AAS) has been associated with a number of physical and psychiatric/behavioural complications, some of which are potentially lethal. Here, we review both observational and experimental studies on human subjects concerned with such side-effects. The only physical complication of AAS use that receives definitive support from such investigations is unfavourable changes in blood lipid profiles. Support for various psychiatric complications has also been provided by a number of cross-sectional studies, most involving comparisons between weight-training individuals who use or do not use AAS. Certain of these complications, in particular hypomania and increased aggressiveness, have been confirmed in some, but not all, randomized controlled studies. Epidemiological attempts to determine whether AAS use triggers violent behaviour have failed, primarily because of high rates of non-participation. Studies regarding the prevalence of AAS use in different populations typically report life-time prevalences of 1-5% among adolescents. However, the life-time prevalence (i.e. use on at least one occasion) is of doubtful relevance in attempting to estimate the number of individuals at risk for side-effects, as most of these complications appear to develop during prolonged use of AAS. Furthermore, it is reasonable to assume that the symptoms and signs of AAS use are often overlooked by healthcare professionals, so that the number of cases of possible AAS-related complications is virtually unknown. These limitations, together with an apparently low prevalence of prolonged AAS use among the general population, indicate that future epidemiological research in this area should focus on retrospective case-control studies and, perhaps, also on prospective cohort studies of populations selected for a high prevalence of AAS use, rather than attempting to perform large-scale population-based studies.
1 Endocrine and anti-fertility studies were carried out on a fluorinated bibenzyl, bifluranol, in rats and mice. 2 A potent anti-prostatic activity of bifluranol was shown to be comparable to diethylstilboestrol (DES). In contrast, its oestrogenic potency by the oral route was about eight times less than that of DES. 3 In comparative short and long-term anti-androgenic and fertility studies in rats and in studies on sexual potency and reproductive performance in male mice, bifluranol given orally was shown to produce fully reversible suppression of accessory sexual structures without impairment of spermatogenesis and fertility. In contrast, DES administered in the same dose reduced spermatogenesis as well as accessory sexual glands. 4 Bifluranol lowered serum luteinising hormone (LH) levels without affecting follicle stimulating hormone (FSH). Under similar conditions DES reduces both LH and FSH levels. Since bifluranol does not antagonize androgen-induced stimulation of the prostate in castrated rats, its anti-prostatic effect is interpreted as a negative, hormonostatic feedback activity, mediated through a selective inhibition of LH secretion.
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