Human male sexual functions do not require aromatization of testosterone: A study using tamoxifen, testolactone, and dihydrotestosterone

Gooren, L. J. G.

doi:10.1007/bf01541754

Cited by 50 publications

(31 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Is it possible that, in addition to interaction between testosterone and oestradiol in negative feedback control of LH, some of the effects of testosterone on sexual interest and arousability are mediated by aromatization of testosterone to oestradiol? Gooren (1985) found that, in eugonadal men, the oestrogen receptor antagonist, tamoxifen, and the aromatase inhibitor, testolactone, had no adverse sexual effects, and that dihydrotestosterone (DHT) was as effective as testosterone in maintaining sexuality in hypogonadal men. He took this to mean that the sexual effects of testosterone within the CNS are mediated by DHT but not by oestradiol.…”

Section: Where Do Androgens Act In the Brain?mentioning

confidence: 99%

The endocrinology of sexual arousal

Bancroft¹

2005

Journal of Endocrinology

344

197

View full text Add to dashboard Cite

The relevance of testosterone, oestradiol and certain peptides (oxytocin (OT), -endorphin and prolactin (PRL)) to sexual arousal in humans is reviewed. In addition to behavioural studies, evidence of distribution of gonadal steroid receptors in the brain and the limited evidence from brain imaging are also considered. Testosterone plays a key role in the adult male, with clear, consistent evidence from studies of hypogonadal and eugonadal men. The roles of testosterone in the development of sexual arousability, and in the aging male, are less clear. The relevance of aromatization and of non-sexual effects of testosterone which might indirectly influence sexual arousal are not well understood. Testosterone in the female presents a more complex, less consistent picture. One possible explanation is a much greater variability across women in responsiveness to testosterone. A 'desensitization hypothesis' to account for the striking gender differences is offered. There is limited evidence of a direct effect of oestradiol on sexual arousability in women. The extent to which testosterone in women acts by conversion to oestradiol or by increase of free oestradiol is not yet clear. The role of peptides in sexual arousal remains uncertain, partly because of the multiple roles and sites of action of most peptides. OT and -endorphin appear to have both excitatory and inhibitory effects. PRL has been proposed as an inhibitory factor via direct inhibition of dopaminergic activity, but the evidence for this is inconclusive. Whereas the traditional concept of 'hormone' continues to apply to the role of testosterone and oestradiol in sexual arousal, peptides present a more complex role.

show abstract

Section: Where Do Androgens Act In the Brain?mentioning

confidence: 99%

The endocrinology of sexual arousal

Bancroft¹

2005

Journal of Endocrinology

344

197

View full text Add to dashboard Cite

show abstract

“…Studies in normal men showed that sexual function is unaffected by estrogen depletion or antagonism, and concluded that the aromatization of T is not required to maintain normal sexual activity in adult men (Gooren, 1985;Bagatell et al, 1994). Likewise, previous reports showed no remarkable sexual dysfunction in men affected by congenital estrogen insensitivity or deficiency (Smith et al, 1994;Carani et al, 1997).…”

mentioning

confidence: 93%

Anatomic relationships between aromatase and androgen receptor mRNA expression in the hypothalamus and amygdala of adult male cynomolgus monkeys

Roselli

Klosterman

Resko

2001

J of Comparative Neurology

View full text Add to dashboard Cite

This study mapped the regional locations of cells expressing cytochrome P450 aromatase (P450AROM) and androgen receptor (AR) mRNAs in the adult male macaque hypothalamus and amygdala by in situ hybridization histochemistry using monkey-specific cRNA probes. High densities of P450AROM and AR mRNA-containing neurons were observed in discrete hypothalamic areas involved in the regulation of gonadotropin secretion and reproductive behavior. P450AROM mRNA-containing neurons were most abundant in the medial preoptic nucleus, bed nucleus of the stria terminalis, and anterior hypothalamic area, whereas AR mRNA-containing neurons were most numerous in the ventromedial nucleus, arcuate nucleus, and tuberomamillary nucleus. Moderate to heavily labeled P450AROM mRNA-containing cells were present in the cortical and medial amygdaloid nuclei, which are known to have strong reciprocal inputs with the hypothalamus. Heavily labeled P450AROM mRNA-containing cells were found in the accessory basal amygdala nucleus, which projects to the cingulate cortex and hippocampus, areas that are important in the expression of emotional behaviors and memory processing. In contrast to P450AROM, the highest density of AR mRNA labeling in the temporal lobe was associated with the cortical amygdaloid nucleus and the pyramidal cells of the hippocampus. All areas that contained P450AROM mRNA-expressing cells also contained AR mRNA-expressing cells, but there were areas in which AR mRNA was expressed but not P450AROM mRNA. The apparent relative differences in the expression of P450AROM and AR mRNA-containing neurons within the monkey brain suggests that T acts through different signaling pathways in specific brain areas or within different cells from the same region.

show abstract

“…Aromatization of testosterone occurs in the brain, but the physiologic role of this is unclear. No specific behavioral issues were reported in men with either estrogen receptor mutations or aromatase deficiency [57,58] and, similarly, no clear effects were identified during experimental investigation of sexual function in normal men [85].…”

Section: Behavioral Effects Of Testosteronementioning

confidence: 92%

Male hormonal contraception: a safe option?

Walton

Anderson

2006

Expert Review of Endocrinology & Metabolism

View full text Add to dashboard Cite

Hormonal male contraception is based on the administration of testosterone alone or more likely with a progestogen. Testosterone has been used for several decades for the treatment of male hypogonadism, with an excellent safety record. Use as part of a contraceptive regimen by healthy people for prolonged periods will necessitate careful re-examination of safety issues. Although potential male contraceptive regimens have been investigated for many years, there have been mostly small-scale studies unable to assess safety. This is now changing, with larger studies of regimens underway. This, and the increasing involvement of the pharmaceutical industry, means that much more data will shortly be forthcoming and it is hoped that this will also provide valuable information relevant to normal male health. The main areas of interest are the cardiovascular system and the prostate, but bone health and body composition are also important, as are behavioral and psychologic aspects. The development of this field also allows the investigation of potential health benefits, which may be related to the use of synthetic androgens with tissue-selective metabolism or action.The launch of a male hormonal contraceptive onto the market has become increasingly likely in recent years. Large-scale efficacy studies are currently underway in China and commercial studies in Europe are due to report their findings next year. One of the major remaining questions concerning this approach is the safety of administering exogenous hormones to men. Despite 40 years of widespread use, safety issues concerning female hormonal contraceptives continue to evolve and the mass media are quick to foster them. Will men be convinced as to the validity and necessity of a similar approach? In reality, most of the safety issues will have to be addressed by postmarketing surveillance, as much of the research in this field is currently in the form of small-scale studies that are not adequately powered to detect safety concerns. Some of the major issues will be discussed. Testosterone preparations are not new drugs and a considerable amount of data has been acquired in respect of administration as androgen replacement in hypogonadal men. Two of the main safety issues of concern for male hormonal contraceptive development are cardiovascular effects and the effect on the prostate gland. However, there are several other aspects to consider, including maintenance of bone and muscle mass, effects on erythropoiesis and behavioral effects. These data are essentially reassuring. Thus, prostate volume in testosterone-replaced hypogonadal men is similar to that in normal men without any evidence of increased risk of malignancy [1]. Likewise, bone mass approaches normal depending on how carefully replacement has been administered [2]. This is despite the marked limitations of the testosterone preparations available, being confined to short-acting injectable esters for the great majority of men. One area that continues to require monitoring is the stimulatory effect of testo...

show abstract

Human male sexual functions do not require aromatization of testosterone: A study using tamoxifen, testolactone, and dihydrotestosterone

Cited by 50 publications

References 15 publications

The endocrinology of sexual arousal

The endocrinology of sexual arousal

Anatomic relationships between aromatase and androgen receptor mRNA expression in the hypothalamus and amygdala of adult male cynomolgus monkeys

Male hormonal contraception: a safe option?

Contact Info

Product

Resources

About