[quote]Hook24 wrote:
Hey Guys, this is the most clear and concise thread I have found regarding E2. It is a sticky from the T Replacement Forum and was written by Happydog.
From Happydog’s Estradiol Sticky.
"The first is that E2 is a powerful testosterone receptor antagonist. What this means is that estradiol binds to androgen receptors and renders them useless. When testosterone binds to an androgen receptor, it activates the receptor and you get the effect you’re looking for. When estradiol binds to that receptor, it blocks testosterone from binding, yet it does not active the receptor, so nothing happens.
This means that if your estradiol is high, no matter how much testosterone you have, it isn’t helping you as it should because too many of your androgen receptors are blocked by estradiol and your free testosterone has no where to go. Testosterone can’t do you any good if it doesn’t have receptors available to activate.
It can even get worse… because high levels of estradiol can cause the downregulation of androgen receptors. This means that your body may respond to higher levels of estradiol by creating fewer androgen receptors as cells are replaced in normal regeneration. In other words, not only does estradiol block the available androgen receptors, it causes your body to produce fewer of them in the future! This is one reason why raising testosterone levels may not have any immediate effect. It may be that your receptors have downregulated and so you’ll need to lower estradiol and increase testosterone in order to get your body to upregulate again and this takes time."
Hopefully I havn’t misinterpretted the information.
[/quote]
I looked for quite some time and couldn’t find anything other than this thread to suggest estrogen binds to androgen receptors. I believe this to be incorrect.
I do believe the other part about down regulation of androgen receptors to be correct, though.
If anyone has anything to suggest estrogen binds to androgen receptors please post it.