This an abstract from a study:
Abstract
The effect of estradiol on prolactin gene transcription in pituitaries from ovariectomized, female rats has been investigated. Analysis of the multiple prolactin mRNA species present in pituitary cells demonstrated that estradiol increases the concentration of all the large, potential nuclear precursors of prolactin mRNA. To further examine possible estradiol effects on prolactin mRNA synthesis, nuclei were isolated from rat pituitaries and allowed to continue RNA synthesis in vitro in the presence of [alpha-32P]UTP. Newly synthesized prolactin mRNA sequences were quantitated by hybridization of [32P]RNA to immobilized plasmid DNA containing prolactin cDNA sequences. After 24 h of estradiol treatment, prolactin mRNA synthesis was increased 4-fold. Estradiol effects on prolactin gene transcription were detected as early as 20 min after injection of the steroid. These findings suggest that estradiol increases prolactin mRNA levels by increasing the transcription of the prolactin gene.
So I would say it would have some effect but it might not totally negate the prolactin problem.
Here's the article if you would like to read it.
http://m.jbc.org/content/257/5/2133.short
The full article is free to DL in pdf
Also useful information.
First lets discuss what a progestin (AKA progestogen) is. A progestin is essentially a derivative of the steroid hormone progesterone, and as such it has progestogenic effects in the body. This is much like something that is a DHT derivative, and therefore has very strong DHT effects (think about DHT-derived AAS). Progesterone is a hormone involved in the female menstrual cycle and pregnancy, and is not something that should be found in men. One of progesterone's purposes is so signal the pituitary gland to produce and secrete a protein hormone called prolactin. Prolactin is another hormone which serves a purpose in pregnant women, and it binds to receptors in breast tissue to signal lactation. This presents a couple of problems for men, which leads to the side effects from tren that are progesterone-based.
The first undesireable side effect commonly discussed is 'tren-dick'. Basically, it is erectile dysfunction resulting from the use of trenbolone due to its progestogenic effects and prolactin secretion. Prolactin has an EXTREME suppressive effect on the libido. Related effects to this include anorgasmia (inability to achieve orgasm), which is again a direct result of increased prolactin levels in the body. The second undesireable side effect is gyno. Yes, gyno is a potential risk with trenbolone even though it does not aromatize into estrogen. This is once again due to prolactin. In addition to prolactin causing lactation, it can and will cause breast tissue to form. This is known as prolactin-related gyno (as opposed to estrogen-related gyno).*
In order to deal with these side effects, I highly reccomend the use of a prolactin antagonist. One of the three: Cabergoline (my favorite, and the one I use exclusively), Pramiprexole (a new prolactin antagonist on the market), and Bromocriptine. Vitamin B6 has also displayed strong anti-prolactin qualities. It is also well known that one can eliminate the risk of prolactin-related gyno by controlling estrogen levels and maintaining a low level. This is*partially*true, as estrogen has an upregulating effect on the progesterone receptor in breast tissue (in layman terms, it makes the receptors more excitable to progesterone). As a result, it is very possible that a very very high estrogen level may upregulate progesterone receptors to the point where even a very small amount of prolactin can set off prolactin-induced gyno. My personal preference: take Cabergoline (or one of the prolactin antagonizers) anyways. Although you may be able to eliminate prolactin-related gyno by keeping estrogen levels under control - it does NOT eliminate or prevent prolactin secretion from the pituitary. This is only a control for the gyno issue. A good prolactin antagonizer such as Prami or Caber run during a tren cycle will prevent any potential prolactin secretion in the first place by operating through dopaminergic pathways.
None of this is mine. Not taking any credit.
