jacshelb said:
So, is that why we have prolactin problems, because tren and deca are progestins that supress natural progesterone production? Is it a kind of prolactin rebound? If not, what causes the prolactin issues? BTW- I did mean prolactin, but this whole thing is admittedly a little confusing to me. Would love to figure it all out. I know the real world effects first hand, but don't fully understand the mechanics.
Thanks,
Jacob
This article seems to give a much broader scope of the terms "progesterone" and progestin then the tunnel vision approach I was using
http://www.mesomorphosis.com/articles/ullis/contrarian-endocrinology-02.htm
Progesterone for Men
Once again, I am not crazy. I know that most of you think of progesterone as an "evil" catabolic and fattening hormone. What many of you may not remember is that the extremely popular anabolic steroid nandrolone decanoate (aka Deca Durabolin or nortestosterone) is in fact classified as a progestin (hormone with progesterone-like activity)! In addition, many progestins given to women in birth control pills and other drugs such as norgestrel and norethidrone are classified as 19-nor-testosterone or 19 nor- progesterone derivatives. Eastern German female Olympic athletes were known to have taken large quantities of these nor-testosterone derivatives to build muscle with the notorious masculinizing side effects that was obvious to all Olympic observers. Modern Olympic testing can now distinguish the difference between nor-progesterone and nor-testosterone derivatives. Since birth control pills aren’t yet on the list of drugs banned from competition, these "women" were able to pass all drug testing without any worries. Of course, I don’t suggest you raid your girlfriends birth control pill case in order to make yourself "feel like Deca". Recent studies at UCLA (9) have shown that different types of birth control pills have different androgenic capacity and can change the Olympic doping standard of testosterone to epitestosterone ratio of six to one with an increase of that ratio.
Are you confused yet? How can one of the most manly of anabolic steroids such as Deca Durabolin be considered a female hormone? How can female birth control pills be used as anabolic steroids? The simple answer to this question is that progesterone is best not considered as a female hormone, but as a hormone with properties somewhere in the middle between testosterone and estrogen. You can tweak the progesterone molecule slightly one way and have a hormone that is androgenic, or tweak it another way and be less androgenic or become more neutral in effect like the natural progesterone in the human body. Progesterone has its reputation as a female hormone due to its role in promoting pregnancy. But natural progesterone is still present in the male and also plays an important role in male physiology, but it has not yet been clearly elucidated. It should be noted that the "masculine" hormone nor-testosterone, that is the basis for the anabolic steroid Deca Durabolin, is actually found in highest concentrations in pregnant women (10).
So how can progesterone like molecules make me big or improve my athletic performance? Are large doses of Deca what you are referring to when you talk about "progesterone for men"? The answer is that nortestosterone drugs and prohormones have disadvantages over testosterone for use in hormone replacement therapy and in athletics / bodybuilding. The main reason nortestosterone is so popular is because of its lower androgenicity. It competes with testosterone for the 5-alpha reductase enzyme that converts testosterone to DHT and instead converts to dihydronortestosterone which is much less androgenic. Therefore you are less likely to experience side effects often associated with testosterone such as acne, hair loss, etc.
However, some people don’t know about nor understand the drawback of nortestosterone. For one thing, it can drastically lower libido. This is not surprising since other progestin based drugs are given to sex offenders to purposely lower their libidos. For male hormone replacement therapy, this can make nortestosterone a big no-no. Most men considering hormone replacement therapy are already suffering from a loss of libido, and nortestosterone can be almost like a castration agent for them. In addition, nortestosterone has a lower aromatization rate than testosterone. Since estrogen can raise HDL levels while androgens tend to lower HDL, this lack of estrogen from nortestosterone can cause HDL levels to drop further than when on testosterone. While temporarily low HDL levels may not be a big concern for a healthy young athlete, this is obviously a bigger concern for older men or those with heart disease risk factors.
Instead of using nortestosterone for hormone replacement therapy, I recommend a combination of natural testosterone and pulses of natural progesterone when testosterone is used. Progesterone, like nortestosterone, competes with testosterone for the 5-alpha reductase enzyme. A combination of testosterone/progesterone could allow for the benefits of increased testosterone while keeping DHT levels balanced. The concept is to help maintain a natural and youthful testosterone/estrogen/progesterone ratios throughout your lifetime. I believe a proper balance is the key to a healthy libido, prostate, and cardiovascular system.
While synthetic progesterone derivatives have been used to lower libido in men (1, 5), I believe that natural progesterone may in fact have the opposite effects in some men. I have heard patient anecdotes and from other medical doctors saying that application of a natural progesterone cream to the scrotum can increase libido and enhance orgasmic pleasure in some men.. I believe that just as high doses of synthetic progesterone derivatives can lower libido, so can low levels of natural progesterone. Natural progesterone can have a calming effect on the nervous system and may help those men who are "rapid ejaculators" or have other anxiety related sexual problems. Restoring or pulsing progesterone may enhance libido, and sexual function. While large doses of synthetic progestins may cause you to get fatter or lose muscle, the role of progesterone in increasing body temperature has been well studied in women (3) and may help bring back resting metabolic rate to a more youthful levels in men as well. Progesterone has the benefit of boosting metabolism but too much can lead to high insulin levels which would likely cancel out any benefits of increased metabolism.
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