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  1. #1
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    Recently I was supplementing 10mg melatonin 30minutes before bed. During this period my libido was absolutely hectic for the first couple of weeks, I'm talking like load after load after load in one session easily.



    I stopped taking melatonin when my libido seemingly decreased and when I read reports of it actually lowering testosterone levels. I am a powerlifter so test levels are a big concern.



    What I was wondering about was the effects of melatonin upon hormone levels and their effects upon libido.



    thanks guys.

  2. #2
    Senior Member Benson's Avatar
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    [quote name='peal' date='Nov 5 2005, 06:24 AM']Recently I was supplementing 10mg melatonin 30minutes before bed. During this period my libido was absolutely hectic for the first couple of weeks, I'm talking like load after load after load in one session easily.

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    [/quote]



    Lets parse this out a little and maybe we can get somewhere.



    1- Why were you taking melatonin? For insomnia or some other reason? 10mg is a fairly hefty dose BTW, most people do pretty well with 3mg.



    2- "load after load after load" I take it you are talking about ejaculation. This is not the same as libido which is usually used to mean desire. Some things that positively effect sexual performance may have no effect at all on libido. You are attributing increased performance with melatonin use which may or may not be likely. Did you also experience an increase in sexual desire?



    3- You stopped taking melatonin when your "libido decreased" Was this a fall off in desire or performance?
    Remember, believe none of what you hear and half of what you see...





  3. #3
    Senior Member vain68's Avatar
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    Lets parse this out a little and maybe we can get somewhere.


    Agreed.
    ...'and by home, you know, I do not mean a lovely house with all the modern conveniences. By home I mean the room or two that have become associated in the child's mind with the mother and father, and the other children, and the cat. And there is a shelf or cupboard where the toys are kept...'
    -Winnicott

  4. #4
    Senior Member Benson's Avatar
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    Perhaps you are confusing melatonin with melanotan? The former has almost no direct prosexual effects that I am aware of while the latter is shaping up to be the designer drug of the next decade...
    Remember, believe none of what you hear and half of what you see...





  5. #5
    Senior Member vain68's Avatar
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    Benson,

    good catch, for some reason when I saw melatonin, I thought MC system without thinking.



    v



    Humbling, very humbling.
    ...'and by home, you know, I do not mean a lovely house with all the modern conveniences. By home I mean the room or two that have become associated in the child's mind with the mother and father, and the other children, and the cat. And there is a shelf or cupboard where the toys are kept...'
    -Winnicott

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    sexual desire was higher, higher ejaculation content, higher performance etc.



    I stopped taking melatonin because I read an article that indicated it would decrease testosterone levels.



    I was taking melatonin as a sleep aid. I have trouble getting to sleep at regular hours, so I used it to control when I would go to sleep.



    10mg was the amount recommended by my pharmacist.

  7. #7
    Senior Member triceptor's Avatar
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    [quote name='peal' date='Nov 5 2005, 03:36 PM']sexual desire was higher, higher ejaculation content, higher performance etc.



    I stopped taking melatonin because I read an article that indicated it would decrease testosterone levels.



    I was taking melatonin as a sleep aid. I have trouble getting to sleep at regular hours, so I used it to control when I would go to sleep.



    10mg was the amount recommended by my pharmacist.

    [snapback]279764[/snapback]

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    10mg.. yikes. I have always heard that 3mg with the upper limits being 6mg and higher actually can have the opposite effect.. almost stimulates you.. also I posted two study abstract at your other duplicated subject thread showing that melatonin may have an anti-aromatase effect at the testis and elevates T levels...
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    if you take 10mg melanotan it would be very interesting ;P

    melatonin isa tough one... because it is kind of a precursor or lets say substitute for those who have defficiency in that subsystem it will help greatly but not to otheres or adverse effect... in lower doses it is supposed to be neuroprotective... higher doses its up in the air... I understand that the body actualy upregulates melatonin destroying enzyme and this is how you become desensetized.
    Man on a mission

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    so I have 5mg tabs, would 5mg be a reasonable dosage before bed?

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    If melatonin improves deep sleep, might that not have a positive effect on LH and FSH; thereby indirectly stimulating T production? Likewise, might it result in more growth hormone release, too?

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    [quote name='Bullwinkle' date='Nov 8 2005, 01:48 PM']If melatonin improves deep sleep, might that not have a positive effect on LH and FSH; thereby indirectly stimulating T production? Likewise, might it result in more growth hormone release, too?

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    [/quote]





    I am led to believe that it would, but only if you aren't getting solid deep sleep already.



    I like using it around exam time, it allows me to control my sleep, which is why I'm using it atm

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    Taken from Wikipedia=



    "Melatonin... has a role in regulating circadian rhythms. Melatonin is a derivative of the amino acid tryptophan."



    "Melatonin can suppress libido by inhibiting secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the anterior pituitary gland -- especially in mammals that have a breeding season when daylight hours are long, such as sheep. Nobel Prize laureate Julius Axelrod performed many of the seminal experiments elucidating the role of melatonin and the pineal gland in circadian rhythms. Beta blockers decrease nocturnal melatonin release."





    "In recent times, melatonin has become available as a drug and a dietary supplement. It appears to have some use against insomnia, jet lag, and circadian misalignment. Melatonin is a powerful antioxidant which can easily cross cell membranes including the blood-brain barrier. It has been studied for the treatment of cancer, immune disorders, cardiovascular diseases, depression, seasonal affective disorder, and sexual dysfunction; the results of most of these studies remain inconclusive. However, it has been shown to clearly ameliorate seasonal affective disorder and circadian misalignment, in studies by Alfred J. Lewy (OHSU) and other researchers."



    "Melatonin is referred to by some biochemists and human physiologists as the master hormone, because it regulates the production of most human hormones, both paracrine and endocrine. In addition, melatonin, taken alone, is an immunoregulator that enhances T cell production somewhat. However, when melatonin is taken in conjunction with calcium, it is a very potent immunostimulator of the T cell response. This is the reason it is used as an adjuvant in many clinical protocols. Because it does not have to be prescribed, and since it is in the public domain, few doctors care to publicize its advantages. For the same reason, few clinical trials have been done to see its effectiveness in treating various diseases, such as cancer, obesity, HIV infection, and others."



    "Fortunately, melatonin exhibits almost no toxic side effects, except for the occurrence of somnolence in most of the population at higher doses. There are as of yet no reports about melatonin toxicity, notwithstanding the dosage administered, nor the amount of time the medication has been taken, except for clinical changes as noted in various studies. Exogenous melatonin does not affect the endogenous melatonin profile in the short or medium-term."

  13. #13
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    Quote Originally Posted by C19H28O2' date='Nov 9 2005, 12:54 PM
    Taken from Wikipedia=



    "Melatonin... has a role in regulating circadian rhythms. Melatonin is a derivative of the amino acid tryptophan."



    "Melatonin can suppress libido by inhibiting secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the anterior pituitary gland -- especially in mammals that have a breeding season when daylight hours are long, such as sheep. Nobel Prize laureate Julius Axelrod performed many of the seminal experiments elucidating the role of melatonin and the pineal gland in circadian rhythms. Beta blockers decrease nocturnal melatonin release."




    anyone?

  14. #14
    Senior Member Benson's Avatar
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    [quote name='peal' date='Nov 9 2005, 10:52 AM'][quote name='C19H28O2' date='Nov 9 2005, 12:54 PM']Taken from Wikipedia=



    "Melatonin... has a role in regulating circadian rhythms. Melatonin is a derivative of the amino acid tryptophan."



    "Melatonin can suppress libido by inhibiting secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the anterior pituitary gland -- especially in mammals that have a breeding season when daylight hours are long, such as sheep. Nobel Prize laureate Julius Axelrod performed many of the seminal experiments elucidating the role of melatonin and the pineal gland in circadian rhythms. Beta blockers decrease nocturnal melatonin release."



    [/quote]



    anyone?

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    [/quote]



    Do you only breed in the summer? IMHO, animal 'libido' studies don't have a lot of application in humans because sexual desire in humans is substantially more complex.
    Remember, believe none of what you hear and half of what you see...





  15. #15
    Senior Member JohnMK's Avatar
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    I'm reasonably sure that my acne (which I hadn't had a problem with in about 6-7 years) fully reared when I started taking 1mg of melatonin per night. There was a lag in onset of acne of mmmm a week or two, perhaps. I've since dropped to 250-500 mcg per night and it's steadily come under control. It might take a while to fully heal what started, but I'm on the mend.



    I am not certain this was caused by melatonin, but it might have been.

  16. #16
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    Benson appears to be on point, based on these abstracts-



    Taken from- Ingenta labs



    "The effects of melatonin on physiological function remain unclear, although the therapeutic potential of melatonin is being increasingly recognized. The aim of the present study is to investigate the effects of exogenous melatonin on the spontaneous release of pituitary hormone in humans. A double blind placebo-controlled protocol was designed to examine 12 adult healthy volunteers and 12 sleep disorder patients who have been treating with low doses of melatonin for 1 year. Either exogenous melatonin or placebo of 1 mg was given at 09:00 hours, followed by the collection of blood samples every 20 min for 4 h. Each blood sample was examined for levels of serum melatonin, PRL, LH, FSH, GH and TSH. LH levels were higher in sleep disorder patients compared with the healthy volunteers. In other pituitary hormones, there were no significant difference between healthy adults and sleep disorder patients. In all subjects, PRL levels were stimulated by acute administration of 1 mg of exogenous melatonin, while the levels of other pituitary hormones were not affected. These results suggested that exogenous melatonin can affect the spontaneous release of LH and PRL in humans. In addition, we demonstrated that 1-year oral melatonin treatment did not affect the responses to the acute administration of melatonin."



    The following taken from- Oxford Medicine Journals





    Long-term melatonin administration does not alter pituitary-gonadal hormone secretion in normal men

    Rafael Luboshitzky1,5, Michal Levi2, Zila Shen-Orr3, Zeev Blumenfeld4, Paula Herer2 and Peretz Lavie2

    1 Endocrine Institute, Haemek Medical Center, Afula 18101, 2 Sleep Research Center, 3 Endocrine Laboratory, Rambam Medical Center, Haifa and 4 The B.Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel



    "The role of melatonin in the regulation of reproduction in humans is still controversial. In the present study the effects of melatonin were examined, 6 mg given orally every day at 1700 h for 1 month in a double-blind, placebo controlled fashion, on the nocturnal secretory profiles of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and inhibin ▀ in six healthy adult men. Serum concentrations of LH, FSH, testosterone and inhibin ▀ were determined before and after treatment every 15 min from 1900 to 0700 h over 3 nights in a controlled dark-light environment with simultaneous polysomnographic sleep recordings. The following sleep parameters were determined: total recording time, sleep latency, actual sleep time, sleep efficiency, rapid eye movement (REM) sleep latency and percentages of sleep stages 2, 3/4 and REM. There were no statistically significant differences in all sleep parameters between baseline and placebo or between baseline and melatonin except for longer REM latency and lower percentage REM at baseline than under melatonin treatment. These are explained as reflecting first-night effect at baseline. The mean nocturnal LH, FSH, testosterone and inhibin ▀ integrated nocturnal secretion values did not change during the treatment period. Likewise, their pulsatile characteristics during melatonin treatment were not different from baseline values. Taken together, these data suggest that long-term melatonin administration does not alter the secretory patterns of reproductive hormones in normal men."



    I believe I read somewhere when studying this hormone back when it first started gaining popularity that there are many anti-aging proponents that believe Melatonin to be the "master hormone" and the pineal gland to be the "master gland". The theory is that by stimulating it, the other glands kind of get stimulated by proxy. At the time, there were some proponents that believe the combination of DHEA and Melatonin to be the "ultimate" legal OTC anti-aging stack.

  17. #17
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    "Recent experimental evidence has shown that penile erection and yawning can also be induced in male rats by drugs that modify serotonin (5-hydroxytryptamine, 5-HT) transmission, in particular, 5-HT receptor agonists that act on the 5-HT1c receptor subtype. It has also been shown that the effect of these drugs on penile erection is often paralleled by increased oxytocin release in plasma. This latter effect seems more related to the stimulation of 5-HT1a and/or 5-HT2 receptors although a role of 5-HT1c receptors cannot be ruled out. In agreement with this hypothesis, the paraventricular nucleus receives a dense 5-HT innervation originating from the raphe nuclei of the medulla oblongata. The above results led to the suggestion that penile erection induced by these drugs is mediated by an increased oxytocinergic transmission."


    (NOTE: oxytocin... plays some role in orgasms -- for both males and females. In males, oxytocin is said to facilitate sperm transport in ejaculation.)



    Long-term melatonin administration does not alter pituitary-gonadal hormone secretion in normal men

    Rafael Luboshitzky1,5, Michal Levi2, Zila Shen-Orr3, Zeev Blumenfeld4, Paula Herer2 and Peretz Lavie2



    1 Endocrine Institute, Haemek Medical Center, Afula 18101, 2 Sleep Research Center, 3 Endocrine Laboratory, Rambam Medical Center, Haifa and 4 The B.Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel



    The role of melatonin in the regulation of reproduction in humans is still controversial. In the present study the effects of melatonin were examined, 6 mg given orally every day at 1700 h for 1 month in a double-blind, placebo controlled fashion, on the nocturnal secretory profiles of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and inhibin ▀ in six healthy adult men. Serum concentrations of LH, FSH, testosterone and inhibin ▀ were determined before and after treatment every 15 min from 1900 to 0700 h over 3 nights in a controlled dark-light environment with simultaneous polysomnographic sleep recordings. The following sleep parameters were determined: total recording time, sleep latency, actual sleep time, sleep efficiency, rapid eye movement (REM) sleep latency and percentages of sleep stages 2, 3/4 and REM. There were no statistically significant differences in all sleep parameters between baseline and placebo or between baseline and melatonin except for longer REM latency and lower percentage REM at baseline than under melatonin treatment. These are explained as reflecting first-night effect at baseline. The mean nocturnal LH, FSH, testosterone and inhibin ▀ integrated nocturnal secretion values did not change during the treatment period. Likewise, their pulsatile characteristics during melatonin treatment were not different from baseline values. Taken together, these data suggest that long-term melatonin administration does not alter the secretory patterns of reproductive hormones in normal men.


    ^^^^

    Had not seen this one before... pretty interesting



    Full txt (.PDF):

    http://humrep.oxfordjournals.org/cgi/reprint/15/1/60





    5-Hydroxytryptophan: a clinically-effective serotonin precursor.



    Birdsall TC.



    73541.2166@compuserve.com



    5-Hydroxytryptophan (5-HTP) is the intermediate metabolite of the essential amino acid L-tryptophan (LT) in the biosynthesis of serotonin. Intestinal absorption of 5-HTP does not require the presence of a transport molecule, and is not affected by the presence of other amino acids; therefore it may be taken with meals without reducing its effectiveness. Unlike LT, 5-HTP cannot be shunted into niacin or protein production. Therapeutic use of 5-HTP bypasses the conversion of LT into 5-HTP by the enzyme tryptophan hydroxylase, which is the rate-limiting step in the synthesis of serotonin. 5-HTP is well absorbed from an oral dose, with about 70 percent ending up in the bloodstream. It easily crosses the blood-brain barrier and effectively increases central nervous system (CNS) synthesis of serotonin. In the CNS, serotonin levels have been implicated in the regulation of sleep, depression, anxiety, aggression, appetite, temperature, sexual behaviour, and pain sensation. Therapeutic administration of 5-HTP has been shown to be effective in treating a wide variety of conditions, including depression, fibromyalgia, binge eating associated with obesity, chronic headaches, and insomnia.


    Clin Endocrinol (Oxf). 1998 Aug;49(2):203-7.



    L-5-hydroxytryptophan does not stimulate LH secretion directly from the pituitary in patients with gonadotrophin releasing hormone deficiency.



    Lado-Abeal J, Grana M, Rey C, Cabezas-Cerrato J.



    Endocrinology and Nutrition Service, Galician General Hospital, Spain. cbbjjl@wpoffice.net.ttuhsc.edu



    OBJECTIVE: There is abundant histological and physiological evidence that serotonin plays a role in the regulation of LH secretion in rats. Studies in human subjects have been few, but their results include the finding that pulsatile administration of L-5-hydroxytryptophan (5-HTP, the immediate precursor of serotonin) amplifies LH secretion in women in the medium-late follicular phase, and that this effect is not due to 5-HTP directly inducing LH secretion by the pituitary. We have investigated whether 5-HTP amplifies LH secretion by enhancing the response of the pituitary to GnRH. PATIENTS: Seven patients aged 20-40 years with hypogonadotrophic hypogonadism (HH) of hypothalamic origin (3 men with Kallmann's syndrome, 2 women without anosmia and with GH deficiency, and 2 women with anorexia nervosa).



    DESIGN: To prime the pituitary, subcutaneous pulsatile GnRH was administered for 7 days at the rate of one 5-20 micrograms pulse every 90 min. The day before the investigation, this regimen was replaced by 1.5-3 micrograms intravenous pulses at the same frequency. On the day of the investigation, 3 ml blood samples were taken every 10 min from 0850 to 19:00 hours. After the first two samples, the intravenous GnRH pulse frequency was increased to one per hour and was maintained at this level throughout the rest of the study. The first 4 h of the study acted as a control phase allowing determination of the pituitary response to GnRH. At 1300 h, 75 mg of the aromatic-L-amino-acid decarboxylase inhibitor carbidopa was administered orally; carbidopa does not cross the blood-brain barrier, and prevents peripheral conversion of 5-HTP to serotonin. At 1600 h, another 75 mg dose of carbidopa was administered, and administration of 8-20 mg pulses of 5-HTP at a rate of one pulse per hour was begun.



    MEASUREMENTS: LH was determined in triplicate by an immunoradiometric assay (IRMA), and LH pulses identified by means of a program developed in our laboratory.



    RESULTS: When pulsatile administration of GnRH was accompanied by administration of carbidopa and 5-HTP, LH pulse amplitude (2.32 +/- 0.71 IU/I) did not differ significantly from its value in either the GnRH+ carbidopa phase (2.58 +/- 1.12 IU/I) or the unaccompanied GnRH phase (2.77 +/- 1.76 IU/I).



    CONCLUSIONS: L-5-hydroxytryptophan-induced amplification of LH secretion in humans is not due to enhancement of the pituitary response to GnRH. The effect of L-5-hydroxytryptophan must therefore be due to its action on the hypothalamus, where it may be hypothesized that it increases GnRH release.



    -Unlike many other neurotransmitters, serotonin has been the subject of relatively little research in connection with the regulation of LH secretion in humans, although its involvement in LH regulation in rats is supported by considerable histological and physiological evidence. However, we recently found that ulsatile administration of L-5-hydroxytryptophan (5-HTP) amplifies LH secretion in women in the follicular phase so long as they have an active GnRH pulse generator. Neither the frequency nor the duration of LH pulses are affected, and the effect on pulse amplitude is not due to 5-HTP directly inducing LH secretion by the pituitary.

    -7 patients with hypogonadotropic hypogonadism of hypothalamic origin; 3 men and 4 women. IV 5-HTP, 8-20 mg.

    -It is well established that serotonin is involved in the regulation of LH secretion in rats, its effects depending on sex and steroid hormone status; whereas in male rats it appears to have merely a permissive role, in females it seems to stimulate LH secretion by acting on the hypothalamus as a neurotransmitter.

    -Although our previous study showed that the amplification of LH secretion by 5-HTP was not due to direct induction of LH release by the pituitary, it did not allow determination of whether 5-HTP was acting on the hypothalamus or was enhancing the pituitary response to GnRH.... In the present study, the LH follicular phase pattern secretion (high frequency and low amplitude pulses) has been reproduced in patients with hypogonadotrophic hypogonadism. The results now presented show that 5-HTP does not enhance the effectiveness of GnRH at the pituitary. It may be pointed out that although the dose of 5-HTP used in this work was less than in other studies in order to minimize side effects, the absence of any effect on LH secretion is unlikely to have been due to dose insufficiency, because the obserbed increase in serum cortisol concentrations shows that the quantity of 5-HTP reaching the brain was sufficient to stimulate the hypothalamic-pituitary-adrenal axis.



    -In conclusion, the results presented here, together with our earlier findings, show that the stimulation of LH secretion in humans by pulsatile administration of 5-HTP is not due to any effect of 5-HTP on the pituitary. 5-HTP must therefore be assumed to act on the hypothalamus, probably by stimulating GnRH secretion.


    Prog Clin Biol Res. 1982;92:167-76.* Related Articles, Links



    * * Melatonin:serotonin interaction during termination of the LH surge in rats.



    * * Walker RF.



    * * This study determined whether melatonin's ability to block phasic secretion of LH is a positive timing factor in the reproductive cycle of the female rat. When melatonin synthesis was delayed by extending the photophase on proestrus, serum LH levels were significantly elevated at 2200h. However, melatonin given at 1900h depressed these levels to control values by 2200h despite the extended photophase. This suggests that melatonin helps terminate the LH surge. Since the effect was blocked by pretreatment with quipazine, a serotonin receptor agonist, melatonin may help terminate the LH surge by blocking serotonin neurotransmission. Furthermore, the effects of melatonin and methiothepin, a serotonin receptor antagonist, on hypothalamic serotonin metabolism were comparable, and opposite from quipazine. Temporal patterns of the LH surge changed two months after pinealectomy. These findings suggest that melatonin contributes to termination of the LH surge by an antiserotonin mechanism. The rising levels of melatonin after dark help terminate serotonin signals, and provide a definitive end point for the LH surge, thus helping entrain the gonadotropin rhythm to the light:dark cycle.

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