ISSN:1663-2818    

DOI:10.1159/000179771

出版商:S. Karger AG    

年代:1983

数据来源: Karger

ISSN:1663-2818    

DOI:10.1159/000179772

出版商:S. Karger AG    

年代:1983

数据来源: Karger

ISSN:1663-2818    

DOI:10.1159/000179773

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The various mechanisms regulating testicular and ovarian androgen secretion are reviewed. Testicular androgen secretion is controlled by luteinizing hormone (LH) and follicle stimulating hormone (FSH), which influence the Leydig cell response to the LH. The contribution of prolactin, growth hormone and thyroid hormones to the Leydig cell function is discussed. The ovarian androgen secretion is regulated in a very similar fashion as the Leydig cell of the testis. Prolactin, however, has an inhibitory effect on androgen secretion in the ovary. The intratesticular action of androgens is linked to spermatogenesis. Sertoli cells, by producing the androgen-binding protein, contribute to the intratubular androgen concentration. Inhibin production of the Sertoli cell is stimulated by androgens. In the ovary, androgens produced by the theca interna are used as precursors for the aromatization of estradiol, which stimulates together with FSH the mitosis of granulosa cells. The feedback control of androgen secretion is complicated, as the direct feedback mechanisms are joined by indirect feedback regulations like the peptide inhibin, which can be stimulated by androgens. Intragonadal mechanisms regulating androgen production are the cybernins for testicles and ovaries. In the testicle, estrogens from the Sertoli cells regulate the Leydig cell testosterone biosynthesis. In the ovary, nonaromatizable androgens are potent inhibitors of the aromatization activity in the granulosa cell. A peptide with a FSH receptor binding inhibiting activity is found in male and female gonads. Finally, LH-RH-like peptides have been found in the testicle, which are capable of inhibiting steroidogenesis. These gonadocrinins are similarly produced in granulosa cells of the ovary.

ISSN:1663-2818    

DOI:10.1159/000179774

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Treatment with an LHRH agonist (HOE-766) alone causes an almost complete blockage of testicular testosterone formation in rat and man. In order to neutralize androgens of adrenal origin, a pure antiandrogen (RU-23908) was given in combination with the LHRH agonist in the rat. At doses where each drug has no or minimal effect alone, prostate and seminal vesicle weight were reduced to 9 and 15 % of control after 5 months of combined treatment, respectively. Among the species studied, man is the most sensitive to the inhibitory effect of treatment with LHRH agonists on testicular steroidogenesis. Near castration levels of serum testosterone and 5 α-dihydrotestosterone are obtained within 1-2 weeks of daily subcutaneous administration of the LHRH agonist [D-Ser(tbu)6, des-Gly-NH210]LHRH ethylamide (HOE-766) in adult men with cancer of prostate. The decrease in serum androgen levels is accompanied by objective remission of the cancer in approximately 75% of cases. In a preliminary study where the LHRH agonist was administered in combination with the pure antiandrogen RU-23908, it was shown that the antiandrogen does not interfere with the LHRH-induced inhibition of serum androgen levels. The ease of application of this new form of hormonal therapy should permit its use at early stages of the disease and thus reduce the development of metastases and androgen-resistant cell clones

ISSN:1663-2818    

DOI:10.1159/000179775

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

In intact adult rats almost all androgen receptor (AR) sites of the rat ventral prostate (RVP) are occupied by endogenous dihydrotestosterone, and about 80% of these sites are nuclear. Nuclear AR disappears rapidly after castration (half-life of 3 h). The amount of cytosolic AR does not change within the initial 36 h, then markedly decreases during the next 2-5 days. An early and specific action of androgen is a remarkable increase of its own receptor. RVP also contains an estradiol receptor (ER) which rapidly disappears after castration and which, contrary to AR, is predominantly localized in the cytosol of stromal elements. The published procedures for steroid receptors grossly underestimate receptors concentrations in normal (NHP) and hyperplastic (BPH) human prostate. We have recently established a reliable method for the measurement of total AR, and we have found no difference in AR concentrations between NHP and BPH. BPH also contains a progesterone receptor and an elusive ER. Finally, we have used specific immunoglobulins in sex hormone binding plasma protein (SBP) for the demonstration of SBP-like immunoreactivity by the indirect immunofluorescence technique. The specific antigenic material was exclusively localized in the cytoplasm of BPH epithelial cells.

ISSN:1663-2818    

DOI:10.1159/000179776

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Androgen production by both testes and adrenals decrease in old age; this is partly the consequence of a decrease in the metabolic clearance rate but plasma levels as well as their response to human chorionic gonadotropin (HCG) and adrenocorticotropic hormone stimulation, respectively, do also decrease. As far as testicular androgen levels are concerned, there exists a large interindividual variation of plasma levels even in old age, some elderly persons having levels comparable to those found in young adults. Others have clearly decreased levels. Causes contributing to their variability are general health, physical and sexual activity, smoking habits, obesity, genetic factors, and intake of drugs. Although in exceptionally healthy persons, both physically and sexually active, testosterone levels may, therefore, not decrease in old age, in the elderly population at large, such a decrease does occur, even when all other factors influencing their levels are controlled. The decrease in testicular androgen secretion appears to have a primary testicular origin as luteinizing hormone levels are slightly, but significantly, increased and the response to HCG decreased.

ISSN:1663-2818    

DOI:10.1159/000179777

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

This paper reviews the relationships between androgen levels, aggressive behaviour and social relationships in ungulates and primates. In these and most other mammalian species, aggressive behaviour is sexually dimorphic with males being generally more aggressive than females. This difference is evident very early in play behaviour. In males, and sometimes also in females, aggressive behaviour varies in relation with reproductive cycles and the hormonal changes which are involved in these cycles. The experimental manipulation of hormonal levels by castration or administration of exogenous hormones gives results that vary according to the species, sex, type of hormone (e.g. aromatizable or non-aromatizable androgens), and other factors (e.g. antlers state in stags). Nevertheless, it has generally been shown that aggressive behaviour in male ungulates depends largely on androgens and that in female ungulates androgen treatment consistently raises social rank, with or without modification in aggressiveness. Primates, on the other hand, seem to be less dependent on androgens for the expression of aggressive behaviour and social status.

ISSN:1663-2818    

DOI:10.1159/000179778

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Truly feminine consciousness of gender identity, normal extragenital erotogenic sensitivity, suppressed or very reduced clitoris sensitivity and reaction, normal reaction of the labia minora and the vagina which deepens with the renewal of intercourse, realization of pleasure climax without clonicotonic orgasm and followed by resolution, and a normal maternal attitude seem to characterize sexual behavior in a complete or almost complete testicular feminization syndrome. These features allow one to clearly distinguish, without ignoring multiple psychologic mechanisms, the factors related to androgens and to estrogens in normal feminine sexual behavior.

ISSN:1663-2818    

DOI:10.1159/000179779

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

During fetal development, androgens exert long-term effects which are either organizational on specific organs during a critical phase of morphogenesis (e.g. sexual differentiation of external genitalia), or programming neural functions or enzyme activities expressed later in life. At all stages of development, which extends from fetal and neonatal stages to pubertal accomplishment, androgens also have activational effects that are immediate, multiple, reversible and dose dependent. Both types of actions are intricate during human development. This review will focus (1) on the intricate morphological and activational roles of androgens on sexual differentiation and pubertal development of the genital tract, external genitalia and mammary glands, and (2) on the organizational effects of androgens on four central nervous system functions: pituitary regulation of liver metabolism, gonadotropin secretions, sex dimorphic behavioral patterns, and ‘sexualization of the brain’. If the molecular basis of the immediate androgenic action is known, depending of androgen receptor’s availability and affinity, little is known of the way androgens exert their influence on either so various morphological processes or neuroendocrine impri

ISSN:1663-2818    

DOI:10.1159/000179780

出版商:S. Karger AG    

年代:1983

数据来源: Karger