: Neurosci Biobehav Rev. 2002 Jan;26(1):31-44. Related Articles, Links
Orgasm-induced prolactin secretion: feedback control of sexual drive?
Kruger TH, Haake P, Hartmann U, Schedlowski M, Exton MS.
Department of Medical Psychology, University of Essen, 45122 Essen, Germany.
Recent studies from our laboratory have investigated the hormonal response to various forms of sexual stimulation, including film, masturbation, and coitus in both men and women. This series of studies clearly demonstrated that plasma prolactin (PRL) concentrations are substantially increased for over 1h following orgasm (masturbation and coitus conditions) in both men and women, but unchanged following sexual arousal without orgasm. Here we discuss evidence suggesting that the PRL response to orgasm may play an important role in the control of acute sexual arousal following orgasm. Supporting this position, chronic elevations of PRL (hyperprolactinemia) produce pronounced reductions in animal sexual activity, and significant reduction of libido and gonadal function in both men and women. These data suggest that PRL may represent a peripheral regulatory factor for reproductive function, and/or a feedback mechanism that signals CNS centres controlling sexual arousal and behaviour. Thus, we propose a theoretical model of the role of PRL as a neuroendocrine reproductive reflex.
(word je libido dus minder als je vaak masturbeert?)
: J Sex Marital Ther. 2000 Jul-Sep;26(3):269-83. Related Articles, Links
Controlled studies on women presenting with sexual drive disorder: I. Endocrine status.
Riley A, Riley E.
Lancashire Postgraduate School of Medicine and Health, University of Central Lancashire, Preston, United Kingdom. email@example.com
A single mid-cycle blood sample was obtained from 15 premenopausal female patients presenting with lifelong absence of sexual drive and from a control group of women with intact sexual drive. Serum levels of testosterone, 5-dihydrotestosterone (5-DHT), 17 beta oestradiol, sex hormone binding globulin, and prolactin were measured and indices of free testosterone and 5-DHT were derived. During the menstrual cycle in which the blood samples were obtained, the study subjects kept a diary of their sexual desire and activities. The only endocrine parameter that is significantly different between the two groups is free testosterone, which is lower in the patients than in the control women. Associations between endocrine parameters and indices of sexual behavior were examined. In the control group, average daily sexual thoughts correlates positively with total testosterone, free testosterone index, and free 5-DHT. Feeling of "need for sex" correlates positively with free 5-DHT index and free testosterone index. Experience of sexual thoughts correlates with need for sex, and average frequency of masturbation correlates negatively with age. In both groups, average coital frequency correlates with free testosterone index.
PMID: 10929575 [PubMed - indexed for MEDLINE]
(vrij testosteron was dus erg laag in vrouwen zonder libido... hmmm in de tijden dat mijn PCOS het ergste was, had ik daar ook last van.. volgens mijn vrindje was het doordat mijn gebonden testosteron hoog was en het vrije verlaagd werd door drop!!! is in NL een beruchte oorzaak voor laag testosteron niveau bij vrouwen EN mannen).
Psychoneuroendocrinology. 2000 Feb;25(2):187-99. Related Articles, Links
Neuroendocrine response to film-induced sexual arousal in men and women.
Exton NG, Truong TC, Exton MS, Wingenfeld SA, Leygraf N, Saller B, Hartmann U, Schedlowski M.
School of Psychology, University of New England, Armidale, Australia.
The psychoneuroendocrine responses to sexual arousal have not been clearly established in humans. However, we have demonstrated previously that masturbation-induced orgasm stimulates cardiovascular activity and induces increases in catecholamines and prolactin in blood of both males and females. We presently investigated the role of orgasm in producing these effects. Therefore, in this study parallel analysis of prolactin, adrenaline, noradrenaline, and cortisol concentrations, together with cardiovascular variables of systolic/diastolic blood pressure and heart rate were undertaken during film-induced sexual arousal in nine healthy adult men and nine healthy adult women. Blood was drawn continuously via an indwelling cannula and connected tubing system passed through a mini-pump. In parallel, the cardiovascular parameters were recorded continuously via a computerised finger-cuff sensor. Subjective sexual arousal increased significantly in both men and women during the erotic film, with sexual arousal eliciting an increase in blood pressure in both males and females, and plasma noradrenaline in females only. In contrast, adrenaline, cortisol and prolactin levels were unaffected by sexual arousal. These data further consolidate the role of sympathetic activation in sexual arousal processes. Furthermore, they demonstrate that increases in plasma prolactin during sexual stimulation are orgasm-dependent, suggesting that prolactin may regulate a negative-feedback sexual-satiation mechanism.
PMID: 10674282 [PubMed - indexed for MEDLINE]
(weer zelfde resultaat.. te veel masturberen geeft negatief resultaat?)
Psychosom Med. 1999 May-Jun;61(3):280-9. Related Articles, Links
Psychosom Med. 1999 May-Jun;61(3):290-1.
Cardiovascular and endocrine alterations after masturbation-induced orgasm in women.
Exton MS, Bindert A, Kruger T, Scheller F, Hartmann U, Schedlowski M.
Department of Medical Psychology, University Clinic Essen, Germany.
OBJECTIVE: The present study investigated the cardiovascular, genital, and endocrine changes in women after masturbation-induced orgasm because the neuroendocrine response to sexual arousal in humans is equivocal. METHODS: Healthy women (N = 10) completed an experimental session, in which a documentary film was observed for 20 minutes, followed by a pornographic film for 20 minutes, and another documentary for an additional 20 minutes. Subjects also participated in a control session, in which participants watched a documentary film for 60 minutes. After subjects had watched the pornographic film for 10 minutes in the experimental session, they were asked to masturbate until orgasm. Cardiovascular (heart rate and blood pressure) and genital (vaginal pulse amplitude) parameters were monitored continuously throughout testing. Furthermore, blood was drawn continuously for analysis of plasma concentrations of adrenaline, noradrenaline, cortisol, prolactin, luteinizing hormone (LH), beta-endorphin, follicle-stimulating hormone (FSH), testosterone, progesterone, and estradiol. RESULTS: Orgasm induced elevations in cardiovascular parameters and levels of plasma adrenaline and noradrenaline. Plasma prolactin substantially increased after orgasm, remained elevated over the remainder of the session, and was still raised 60 minutes after sexual arousal. In addition, sexual arousal also produced small increases in plasma LH and testosterone concentrations. In contrast, plasma concentrations of cortisol, FSH, beta-endorphin, progesterone, and estradiol were unaffected by orgasm. CONCLUSIONS: Sexual arousal and orgasm produce a distinct pattern of neuroendocrine alterations in women, primarily inducing a long-lasting elevation in plasma prolactin concentrations. These results concur with those observed in men, suggesting that prolactin is an endocrine marker of sexual arousal and orgasm.
PMID: 10367606 [PubMed - indexed for MEDLINE]
(case closed? geringe invloed op testosteron, grote invloed op prolactine)