Nice find. It seems to be way more difficult to apply HCG right than we thought. I saw studies where people are given 3000 IU (I recently saw one with 5000 IU ED) hCG for a few weeks which should definitely be enough to suppress T production but it didn’t happen (at least not in that limited time frame, think it was 3-4 weeks). As I stated above: the effect is highly individual which shows is again how important bloods are.
If we are on the topic of hCG, there’s one thing I want to point out/discuss.
I repeatedly saw the mantra “AIs won’t stop the aromatization induced by hCG” on this forum and I’d like to get a rationale for that as I couldn’t verify this and my understanding would suggest otherwise. I’ll give my opinion:
HCG increases E2 before it increases T. Several studies show that E2 is highest 24 h after HCG dosing and T 72 h. (Won’t link that) Here you can see an example of acute stimulation of aromatization by hCG in Leydig cells independent of T production:
This could mean that the LH receptor regulates aromatase expression and voila, it does:
With 50 ng/ml oLH, a large augmentation (twofold) of the P450arom mRNA level either without or with testosterone was observed.
With that in mind the only question becomes if AIs get into the Leydig cells (primary T and E2 producers in man) so they can inhibit the aromatase there.
Since the next study shows that non-steroidal AIs readily cross the blood brain barrier, it’s safe to assume they pass the blood testis barrier. They are lipophilic and only anastrozole gets actively transported out of the brain. (I couldn’t find studies about the concentration measured in the testis)
All this info leads me to believe that AIs do
- Get into the Testis and Leydig cells
- Inhibit the aromatase there
- Therefore inhibit aromatization by hCG
Finally this paper shows that AIs do prevent the increase of E2 caused by hCG
In the hCG group, the rate of testicular aromatase activity and testicular E2 level were higher and the diameter of seminiferous tubules was smaller than in the control group. However, these changes were not observed in the hCG+A.I. group
If some of you have evidence suggesting the contrary I’m open to change my opinion.
@anon18050987 I learned a lot too, thanks!
I got a few things I’d like to discuss in the near future: Glucucorticoids (find them extremely interesting and complicated, also in combination with androgens) and then a smaller one would be thyroid hormones (here we could also discuss differences with synthetic and swine derived (I heard it’s a difference but I didn’t research yet, don’t know what it contains right now). I’ll open up new threads then and I’d appreciate your opinion there too.