The endocrinology of sexual arousal

In the paper

“Mood was significantly improved with the higher testosterone dose for ratings of both depression and 'positive well-being'.”

What the sources say

• Supported

  The results text accompanying Tables 3 and 4 reports that the 300 µg/day dose significantly improved both positive well-being and depressed mood compared with placebo (P=0.04 and P=0.03, respectively). This matches the claim about the higher dose. (LLM, conf=0.94)

  cites Shifren et al. (2000) source

In the paper

“Testosterone plays a key role in the adult male, with clear, consistent evidence from studies of hypogonadal and eugonadal men.”

In the paper

“Early studies were based on the maximum change in penile circumference as a measure of erectile response; they found little difference between hypogonadal men with and without testosterone replacement.”

In the paper

“There is limited evidence of a direct effect of oestradiol on sexual arousability in women.”

In the paper

“consistent with testosterone being necessary for normal levels of sexual interest (and arousability).”

In the paper

“This suggested that the plasma level of testosterone needed to avoid the sexual effects of testosterone withdrawal was substantially lower than the pre-treatment baseline level.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bagatell et al. (1994a)

In the paper

“Such studies consistently show a reduction in the level of sexual interest during testosterone withdrawal, usually evident within 3 to 4 weeks”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bancroft 2003

In the paper

“Testosterone in the female presents a more complex, less consistent picture.”

In the paper

“This is consistent with most men having more circulating testosterone than they need for the maintenance of normal sexual function.”

In the paper

“PRL has been proposed as an inhibitory factor via direct inhibition of dopaminergic activity, but the evidence for this is inconclusive.”

In the paper

“OT and -endorphin appear to have both excitatory and inhibitory effects.”

In the paper

“It is noteworthy that, as yet, there has been no adequate placebo-controlled evaluation of the effects of testosterone replacement on sexuality in older men (Institute of Medicine 2004).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Institute of Medicine 2004

In the paper

“In one small placebo-controlled study of eugonadal men with the primary complaint of low sexual desire, O 'Carroll & Bancroft (1984) found a modest but significant increase in sexual desire with testosterone treatment.”

What the sources say

• ?Not checked — no full text of the sourcecites O 'Carroll & Bancroft (1984) source

In the paper

“The relatively predictable effects of testosterone withdrawal and replacement in younger adult men gives way to a more complex, or at least less wellunderstood picture in older men.”

In the paper

“In the second (Halpern et al. 1993), a longitudinal study over 3 years, with 6-monthly assessments, they found the reverse; the stage of pubertal development was much more predictive of sexual interest and behaviour than the free testosterone index.”

What the sources say

• ?Not checked — no full text of the sourcecites Halpern et al. 1993 source

In the paper

“Schiavi et al. (1990), in a study of healthy, medication-free men aged 45 to 74 years, found a clear decline in sexual interest, arousability and activity with age.”

What the sources say

• ?Not checked — no full text of the sourcecites Schiavi et al. (1990) source

In the paper

“Gooren (1988), in a study of hypogonadal teenage males, found that boys with primary hypogonadism showed less response to testosterone replacement than boys with secondary hypogonadism.”

What the sources say

• ?Not checked — no full text of the sourcecites Gooren (1988) source

In the paper

“This showed significantly more rigid and longer duration erectile responses with testosterone replacement.”

What the sources say

• ?Not checked — no full text of the sourcecites Carani et al. 1995 source

In the paper

“Bagatell et al. (1994a) used the gonadotrophinreleasing hormone (GnRH) antagonist, NalGlu, to suppress testosterone levels in eugonadal men over a 6-week period.This lowered sexual interest and associated sexual activity.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bagatell et al. (1994a)

In the paper

“This suggested an age-related decline in testosteronedependent central arousability (i.e.'excitatory tone').”

In the paper

“Schiavi et al. (1990) also found an age-related decline in NPT.”

What the sources say

• ?Not checked — no full text of the sourcecites Schiavi et al. (1990) source

In the paper

“O 'Carroll & Bancroft (1984) found no improvement in erections with testosterone treatment in eugonadal men with ED.”

What the sources say

• ?Not checked — no full text of the sourcecites O 'Carroll & Bancroft (1984) source

In the paper

“The evidence is fairly clear that in men who have gone through normal puberty and who have not yet been affected by aging, testosterone plays an important role in their sexual interest and associated sexual arousability.”

In the paper

“In a subsequent study of women starting on OCs, where a pre-OC baseline was established, negative effects on sexual interest and mood were the best predictors of discontinuation of the OC (Sanders et al. 2001).”

What the sources say

• ?Not checked — no full text of the sourcecites Sanders et al. 2001 source

In the paper

“These results suggest that, at least in those women in whom testosterone has an effect on their sexuality, cyclical variation in testosterone levels should be manifested by cyclical patterns of sexual interest and/or responsiveness.”

In the paper

“In the female, in comparison with the male, we find inconsistent and often contradictory evidence.”

In the paper

“However, in none of these studies was there any assessment of the pre-menopausal testosterone decline.”

In the paper

“Of more relevance, five of the breast feeders reported reduced sexual interest, and their testosterone and androstenedione levels were consistently and significantly lower than the breast feeders who reported no reduction in sexual interest.”

What the sources say

• ?Not checked — no full text of the sourcecites Alder et al. (1986) source

In the paper

“The oestrogen+testosterone and testosterone only conditions showed significantly higher levels of sexual interest, fantasy and arousal than either the oestrogen only or placebo conditions.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sherwin et al. (1985)

In the paper

“A number of behavioural studies have reported a decline in sexual interest in women as they age (see Bancroft 1989, Bancroft et al. 2003).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bancroft 1989
• ?Not checked — no full text of the sourcecites Bancroft et al. 2003 source

In the paper

“A much more limited literature looks at the correlation between testosterone level and sexuality through the cycle, and it is very inconsistent (for review see Bancroft 2003).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Bancroft 2003

In the paper

“However, there is no predictable decline in ovarian androgens following the menopause (Bancroft & Cawood 1996, Burger et al. 2000).”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft & Cawood 1996 source
• ?Not checked — no full text of the sourcecites Burger et al. 2000 source

In the paper

“There is also a tendency across studies for indices of sexual interest to be highest during the follicular phase or around ovulation, though with considerable individual variability in this respect.”

In the paper

“The evidence from such studies on the role of testosterone in sexual interest and response is inconsistent.”

In the paper

“In their longitudinal study of women going through the menopausal transition, assessed over a 9-year period, with an average starting age of 48 years, Dennerstein et al. (2003) found no relation between androgen levels and any aspect of sexual functioning.”

What the sources say

• ?Not checked — no full text of the sourcecites Dennerstein et al. (2003) source

In the paper

“In the substantial literature on the pattern of sexual interest and behaviour through the menstrual cycle there are many inconsistencies, and Hedricks (1994) has discussed various methodological explanations for them.”

What the sources say

• ?Not checked — no full text of the sourcecites Hedricks (1994) source

In the paper

“A number of cross-sectional studies, using multivariate methods of analysis, have found no relation between testosterone and changing levels of sexual interest (Cawood & Bancroft 1996, Kirchengast et al. 1996, Dennerstein et al. 1997).”

What the sources say

• ?Not checked — no full text of the sourcecites Cawood & Bancroft 1996 source
• ?Not checked — no full text of the sourcecites Kirchengast et al. 1996 source
• ?Not checked — no full text of the sourcecites Dennerstein et al. 1997 source

In the paper

“although there is consistent evidence of an increase in vaginal dryness related to the change in oestradiol levels (Dennerstein et al. 2003).”

What the sources say

• ?Not checked — no full text of the sourcecites Dennerstein et al. 2003 source

In the paper

“Eight healthy women with normal testosterone levels, given sublingual doses of testosterone in a placebo-controlled experiment, showed effects of increased testosterone on genital response to erotic stimuli occurring 3-4 h after the peak increase in plasma testosterone (Tuiten et al. 2000).”

What the sources say

• ?Not checked — no full text of the sourcecites Tuiten et al. 2000 source

In the paper

“There is consistent evidence that combined low-dose oral contraceptives (OCs) lower free testosterone (e.g.Bancroft et al. 1991).”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft et al. 1991 source

In the paper

“Alder et al. (1986) assessed women prospectively for 6 months post-partum.Not surprisingly, given the effects of lactation on ovarian function, bottle feeders had higher testosterone and androstenedione levels than the breast-feeding mothers.”

What the sources say

• ?Not checked — no full text of the sourcecites Alder et al. (1986) source

In the paper

“In addition, factors such as body weight and insulin resistance influence this ovarian androgen production (for a brief review of the evidence see Bancroft & Cawood 1996).”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft & Cawood 1996 source

In the paper

“Similar explanations as discussed for their male studies could apply here, but in addition there is a crucial methodological issue of timing of blood sampling for testosterone in relation to the ovarian cycle”

In the paper

“There is a relatively consistent finding that sexual activity is lowest during the menstrual phase.”

In the paper

“They did not differ in measures of sexual activity with a partner or orgasm.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sherwin et al. (1985)

In the paper

“But if lowered free testosterone is the explanation this illustrates once again that such reduction is only relevant in a proportion of women.”

In the paper

“The limited evidence of the effectiveness of testosterone in treating ED is inconsistent.”

In the paper

“and their longitudinal study of girls post-menarche where the reverse relations to testosterone were found (Halpern et al. 1997).”

What the sources say

• ?Not checked — no full text of the sourcecites Halpern et al. 1997 source

In the paper

“In studies of men showing some degree of hypogonadism in association with ED, Carani et al. (1990a) and Morales et al. (1994a) found improvement in erectile function in a minority of cases.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Carani et al. (1990a)
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Morales et al. (1994a)

In the paper

“Whether pre-or post-menopausal, therefore, the woman with both ovaries removed is in a state of relative gonadal steroid deficiency.”

In the paper

“Adrenal androgens have been shown, in a number of studies (Crilly et al. 1979, Orentreich et al. 1984, Bancroft & Cawood 1996, Sulcová et al. 1997, Burger et al. 2000) to decline with age over a relatively wide age span.”

What the sources say

• ?Not checked — no full text of the sourcecites Crilly et al. 1979 source
• ?Not checked — no full text of the sourcecites Orentreich et al. 1984 source
• ?Not checked — no full text of the sourcecites Bancroft & Cawood 1996 source

In the paper

“However, the mid-cycle rise in testosterone is associated with other hormonal changes, and hence correlational studies may not discriminate between direct effects of mid-cycle testosterone levels, and the effects of other mid-cycle changes, such as the rise in oestradiol.”

In the paper

“A crucial change in the function of the interstitial cells of the ovary from pre-to post-menopause complicates the picture.”

In the paper

“Stuart et al. (1987) and Schreiner-Engel et al. (1989) found no difference in testosterone levels between women presenting with low sexual interest and controls”

What the sources say

• ?Not checked — no full text of the sourcecites Stuart et al. (1987) source
• ?Not checked — no full text of the sourcecites Schreiner-Engel et al. (1989) source

In the paper

“Controlled studies of the treatment with testosterone of women presenting with sexual problems have been few.”

In the paper

“androgen receptors appear to be widespread in the primate and human brain, including various cortical areas”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Finley & Kritzer 1999
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sarrieau et al. 1990
• ?Not checked — no full text of the sourcecites Puy et al. 1995 source

In the paper

“There was also staining in the paraventricular and supra-optic nuclei in the males, which was apparently absent in the females.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Fernandez-Guasti et al. (2000)

In the paper

“Their findings were broadly similar to those of Michael et al. (1989).”

What the sources say

• ?Not checked — no full text of the sourcecites Roselli et al. (2001) source

In the paper

“This gender difference was particularly marked in the lateral and medial mammillary nuclei.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Fernandez-Guasti et al. (2000)

In the paper

“In men, intense androgen receptor immunoreactivity was found in neurons of the horizontal limb of the diagonal band of Broca, and of the lateral mamillary and medial mamillary nuclei.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Fernandez-Guasti et al. (2000)

In the paper

“They found little difference between these three groups in the distribution or concentration of ARmRNA, and concluded that in the monkey brain this androgen receptor is not regulated at the transcriptional level by androgen.”

What the sources say

• ?Not checked — no full text of the sourcecites Abdelgadir et al. (1999) source

In the paper

“Hence, some of the sexual effects of testosterone may indirectly result from these mood effects.”

In the paper

“and energy level, well-being and appetite were significantly higher in the two groups receiving testosterone than in the oestrogen only or placebo groups (Sherwin & Gelfand 1985b).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sherwin & Gelfand 1985b

In the paper

“It is also becoming increasingly clear that the sexuality of women is powerfully influenced by mood, energy and well-being, as well as by other psychological mechanisms.”

In the paper

“The limited evidence of androgen receptor distribution in humans includes two studies of the temporal cortex, both of which found substantial amounts of androgen receptor protein (Sarrieau et al. 1990, Puy et al. 1995).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sarrieau et al. 1990
• ?Not checked — no full text of the sourcecites Puy et al. 1995 source

In the paper

“Testosterone also appears to have a mood and energy-enhancing effect in women.”

In the paper

“Riley & Riley (2000) found a marginally lower free androgen index (FAI) in women complaining of life-long absence of sexual drive than in controls.”

What the sources say

• ?Not checked — no full text of the sourcecites Riley & Riley (2000) source

In the paper

“though in the rat greater amounts of aromatase activity are found in the male than the female, in all areas examined except the medial preoptic nucleus (Roselli & Resko 1993).”

What the sources say

• ?Not checked — no full text of the sourcecites Roselli & Resko 1993 source

In the paper

“The sexual effects could therefore have been secondary to improvements in general well-being and energy.”

In the paper

“Overall, there was greater individual variability in the intensity of receptor staining in the women than in the men.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Fernandez-Guasti et al. (2000)

In the paper

“One obvious explanation is that women vary in the extent to which their sexuality is influenced by testosterone, and several examples of evidence supporting this have been presented.”

In the paper

“The transdermal route used in this study has the advantage of producing more physiological and more stable serum testosterone levels than the intramuscular routes used in most other studies, where supra-physiological peaks soon after injection are followed by gradual decline.”

In the paper

“In most areas, women revealed less staining of receptor protein.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Fernandez-Guasti et al. (2000)

In the paper

“Their localization of the ARmRNA was again broadly similar to the distribution of androgen activity reported by Michael et al. (1989).”

What the sources say

• ?Not checked — no full text of the sourcecites Abdelgadir et al. (1999) source

In the paper

“This may account for why, in several studies of younger women, the relationship between testosterone and sexuality was most apparent in women whose sexuality was unproblematic (e.g.Bancroft et al. 1980, Tuiten et al. 1996, Riley & Riley 2000).”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft et al. 1980 source
• ?Not checked — no full text of the sourcecites Tuiten et al. 1996 source
• ?Not checked — no full text of the sourcecites Riley & Riley 2000 source

In the paper

“they concluded that the medial pre-optic and ventro-medial hypothalamic nuclei, the bed nucleus of the stria terminalis, and the cortical, medial and accessory amygdaloid nuclei were the main sites at which the effects of testosterone are mediated predominantly by oestradiol.”

What the sources say

• ?Not checked — no full text of the sourcecites Michael et al. (1989) source

In the paper

“Mood was significantly better with all three hormone regimes (testosterone, oestrogen+testosterone and oestrogen) compared with placebo (Sherwin & Gelfand 1985a)”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sherwin & Gelfand 1985a

In the paper

“As yet, there are no comparative data on the distribution of aromatase activity in women or female primates”

In the paper

“It has been known for some time, however, that oestradiol and progesterone can, in addition, have much more rapid effects directly on the cell membrane (Dufy & Vincent 1980).”

What the sources say

• ?Not checked — no full text of the sourcecites Dufy & Vincent 1980 source

In the paper

“Those women who are behaviourally responsive to testosterone respond to levels of testosterone which would be totally ineffective in men.”

In the paper

“Serotonin does therefore appear to be involved in the refractory period of the male.”

In the paper

“Evidence of the effects of oestrogens on the sexuality of the human male, while limited, consistently suggests a negative effect of exogenous oestrogens.”

In the paper

“Also, men with aromatase deficiency or oestrogen resistance show raised LH and follicle-stimulating hormone (see Roselli et al. 2001).”

What the sources say

• ?Not checked — no full text of the sourcecites Roselli et al. 2001 source

In the paper

“Thus the increase in PRL following orgasm can be seen as an epiphenomenon of post-orgasmic inhibition of DA activity, and not a hormonal mechanism of functional significance.”

In the paper

“The evidence for OT being important in sexual arousal, response and behaviour is, however, less consistent.”

In the paper

“In general, the subsequent animal research has shown similar negative effects of both exogenous and endogenous opiate administration, in male and female animals, with confirmatory evidence from blocking such effects with opiate antagonists such as naloxone, as well as withdrawal effects comparable with those in humans.”

In the paper

“Oestradiol appears to play a key role in the negative feedback control of testosterone.”

In the paper

“So far, therefore, there is only limited overlap between localization of testosterone effects in the brain when comparing androgen receptors and functional brain-imaging studies.”

In the paper

“In long-term castrated rhesus monkeys, physiological doses of testosterone do not reduce LH unless a small amount of oestradiol is also given (Resko et al. 1977).”

What the sources say

• ?Not checked — no full text of the sourcecites Resko et al. 1977 source

In the paper

“They also found deactivation of the left inferior frontal gyrus, suggestive of reduced inhibition of sexual arousal, but only in the controls and treated patients.”

What the sources say

• ?Not checked — no full text of the sourcecites Redoute et al. (2005) source

In the paper

“Physiological levels of testosterone may be necessary for a more generalized pattern of interactive brain activity, much of which is not dependent on direct testosterone effects.”

• Also stated in: § Testosterone · hedged

  “In addition, physiological levels of testosterone may be necessary for a more generalized pattern of interactive brain activity, much of which is not dependent on direct testosterone effects.”

In the paper

“The EE only regime was significantly better than the others in improving sexual interest, enjoyment, orgasmic frequency and also mood.”

What the sources say

• ?Not checked — no full text of the sourcecites Dennerstein et al. (1980)

In the paper

“This may in part reflect methodological limitations of brain imaging; some relevant areas of the brain, especially the hypothalamus, are more difficult to image in this way.”

In the paper

“They found greater activation in the controls and the treated hypogonadal men than the untreated, in the right orbitofrontal cortex, insula and claustrum.”

What the sources say

• ?Not checked — no full text of the sourcecites Redoute et al. (2005) source

In the paper

“However, for that to be the case PRL would need to increase DA activity, which is incompatible with the postulated function of feedback control of sexual drive.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Kruger et al. (2002)

In the paper

“Given the strong relationship between mood and sexuality, which has been demonstrated particularly in women (e.g.Bancroft et al. 2003)”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft et al. 2003 source

In the paper

“Apart from the anterior pituitary, the synthesis of -endorphin is limited to two cell groups in the brain, one in the arcuate nucleus of the hypothalamus, the other in the nucleus of the solitary tract in the brainstem.”

In the paper

“In both men, activation of the inferior frontal lobe, cingulate gyrus, insula and corpus callosum was greater with testosterone replacement.”

What the sources say

• ?Not checked — no full text of the sourcecites Park et al. (2001) source

In the paper

“It would appear to indicate that the effects of oestradiol on sexual interest are dose related.”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Sherwin (1991)

In the paper

“So far, no changes in plasma levels of -endorphin have been found during sexual arousal or orgasm in men (Kruger et al. 1998) or women (Exton et al. 1999).”

What the sources say

• ?Not checked — no full text of the sourcecites Kruger et al. 1998 source
• ?Not checked — no full text of the sourcecites Exton et al. 1999 source

In the paper

“The animal literature is notable for its relative lack of studies on inhibitory mechanisms (Bancroft 1999).”

What the sources say

• ?Not checked — no full text of the sourcecites Bancroft 1999 source

In the paper

“This suggests that desensitization might occur later in life, at least to some extent, and hence not just as an early 'organizing effect'.”

In the paper

“It is therefore noteworthy that the post-orgasmic rise in PRL was very similar in men and women (Kruger et al. 1998, 2003a, Exton et al. 1999).”

What the sources say

• ?Not checked — no full text of the sourcecites Kruger et al. 1998 source
• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Kruger et al. 2003a
• ?Not checked — no full text of the sourcecites Exton et al. 1999 source

In the paper

“This would suggest that any reduction of dopaminergic activity is only part of the picture.”

In the paper

“post-orgasmic rise in PRL was very similar in men and women (Kruger et al. 1998, 2003a, Exton et al. 1999).”

What the sources say

• ?Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  cites Kruger et al. 1998, 2003a
• ?Not checked — no full text of the sourcecites Exton et al. 1999 source

In the paper

“Evidence of 'tolerance' developing to supra-physiological levels of testosterone was reported in several of the hormone replacement studies reviewed earlier (e.g.Brincat et al. 1984, Sherwin & Gelfand 1987).”

What the sources say

• ?Not checked — no full text of the sourcecites Brincat et al. 1984 source
• ?Not checked — no full text of the sourcecites Sherwin & Gelfand 1987 source

In the paper

“Although, in such cases there are a number of factors which could impair normal sexual development, this evidence is consistent with there being some degree of desensitization to the high fetal levels of testosterone, which fall and remain low after birth when the CAH is treated.”