Steroid Profile Primobolan

[Type-IIx]

So I've been told now repeatedly. There were other compounds involved that likely affect serum E2. If this is the only evidence that exists, mine outweighs it. So far, from the limited data, all I can speculate is that: A) not many guys actually do bloodwork, at least on Primo, and/or B) nobody actually has real Primo.

and of course C) [most likely in my estimation] Primo does not actually lower serum E2

 

[GreenAmine]

Hey bro, please don't feel that I am unfairly singling you out. I only am doing so because I know you are an intelligent guy. But do you have any bloodwork or references for any of this? I have been collecting bloodwork on primo and haven't yet seen this to be supported by anything but an avalanche of anecdotes.

No worries at all man, I like this type of discussion. My TRT bloodwork does not include estrogen (honestly because I don't care about the numbers as long as I feel well), so I unfortunately cannot offer anything there.

From my experience, when I take too much primo, I get low E effects (achy joints, anhedonia, libido issues, etc.), and, based solely on research and my own knowledge of biochem, I am semi-certain that either primo itself or (more likely) 1 or more metabolites of primo is acting as a competitive inhibitor of aromatase.

Several of the metabolites of primo structurally resemble T and androstenedione, with a ketone at C3 and C17. These ketones are crucial for binding to aromatase, hydrogen bonding to Asp-309 and Met-374 residues. The alkene can also help with pi-stacking with aromatic residues in the binding site.

Paper listing metabolites of primo (just the abstract; I'm not at work, so can't access the full paper):

Studies on anabolic steroids--4. Identification of new urinary metabolites of methenolone acetate (Primobolan) in human by gas chromatography/mass spectrometry - PubMed

The metabolism of methenolone acetate (17 beta-acetoxy-1-methyl-5 alpha-androst-1-en-3-one), a synthetic anabolic steroid, has been investigated in man. After oral administration of a 50 mg dose of the steroid to two male volunteers, twelve metabolites were detected in urine either in the...

pubmed.ncbi.nlm.nih.gov

This paper states that primo does NOT bind to aromatase:

"Derivatives that do not serve as an aromatase substrate include methenolone acetate (Primobolan®. Bayer Yakuhin, Ltd, Osaka, Japan), stanozolol (Winstrol®), and oxandrolone"

Metabolism of methenolone acetate in a veal calf - PubMed

The use of anabolic steroids has been banned in the European Union since 1981. In this study, the metabolism of the anabolic steroid methenolone acetate, was investigated in a male veal calf. After daily oral administration of methenolone acetate, three main metabolites were detected in both...

pubmed.ncbi.nlm.nih.gov

So I'm hypothesizing that it's the metabolites of primo that act as inhibitors.

 

[Type-IIx]

No worries at all man, I like this type of discussion. My TRT bloodwork does not include estrogen (honestly because I don't care about the numbers as long as I feel well), so I unfortunately cannot offer anything there.

From my experience, when I take too much primo, I get low E effects (achy joints, anhedonia, libido issues, etc.), and, based solely on research and my own knowledge of biochem, I am semi-certain that either primo itself or (more likely) 1 or more metabolites of primo is acting as a competitive inhibitor of aromatase.

Several of the metabolites of primo structurally resemble T and androstenedione, with a ketone at C3 and C17. These ketones are crucial for binding to aromatase, hydrogen bonding to Asp-309 and Met-374 residues. The alkene can also help with pi-stacking with aromatic residues in the binding site.

Paper listing metabolites of primo (just the abstract; I'm not at work, so can't access the full paper):

Studies on anabolic steroids--4. Identification of new urinary metabolites of methenolone acetate (Primobolan) in human by gas chromatography/mass spectrometry - PubMed

The metabolism of methenolone acetate (17 beta-acetoxy-1-methyl-5 alpha-androst-1-en-3-one), a synthetic anabolic steroid, has been investigated in man. After oral administration of a 50 mg dose of the steroid to two male volunteers, twelve metabolites were detected in urine either in the...

pubmed.ncbi.nlm.nih.gov

That's the best evidence I've seen or heard yet. I may look more into that mechanism too. Where I started was looking at some of the some of the metabolic commonalities between EQ, Primo, and Masteron (all contain a secondary 17β-hydroxy group) as they're all reported as acting as AIs and concluded that 17β-hydroxylation of 17-ketosteroids is a common pathway resulting in 17-keto product predominantly reducing back to the 17β-hydroxy steroid (increasing the androgen-estrogen ratio). Thoughts?

 

[GreenAmine]

That's the best evidence I've seen or heard yet. I may look more into that mechanism too. Where I started was looking at some of the some of the metabolic commonalities between EQ, Primo, and Masteron (all contain a secondary 17β-hydroxy group) as they're all reported as acting as AIs and concluded that 17β-hydroxylation of 17-ketosteroids is a common pathway resulting in 17-keto product predominantly reducing back to the 17β-hydroxy steroid (increasing the androgen-estrogen ratio). Thoughts?

That's a good train of thought. As far as the reduction from a ketone back to a hydroxy is concerned, I haven't delved into that at all (in this context, anyway). Since enzymes - in this case, a dehydrogenase - can catalyze a reaction in either direction, it's *technically* possible that, while in the binding site, it converts back to the hydroxyl.

However, from my understanding, enzymatic reactions typically occur in only 1 direction, either because of direct consumption of the product (causing an immediate and continuous equilibrium imbalance) or because of an unfavorable ∆G in the reverse direction.

 

[GreenAmine]

B) nobody actually has real Primo.

I can't always tell when someone is being facetious, so please forgive me if that's the case here. If not, I can say that I have everything that I order tested by UPLC-HRAM-MS, and the Bayer Rimobolan I have has been confirmed by that instrument (mass error < 1 ppm). All of my anecdotal evidence is from this primo.

 

[Type-IIx]

I can't always tell when someone is being facetious, so please forgive me if that's the case here. If not, I can say that I have everything that I order tested by UPLC-HRAM-MS, and the Bayer Rimobolan I have has been confirmed by that instrument (mass error < 1 ppm). All of my anecdotal evidence is from this primo.

Facetious here, yes. It's because the common thread in the disparate but small set of blood work data I've collected on primo or primo+test is so many remarking "looks like you got Test!" Because estradiol is always high along with total test.

 

[Type-IIx]

That's a good train of thought. As far as the reduction from a ketone back to a hydroxy is concerned, I haven't delved into that at all (in this context, anyway). Since enzymes - in this case, a dehydrogenase - can catalyze a reaction in either direction, it's *technically* possible that, while in the binding site, it converts back to the hydroxyl.

However, from my understanding, enzymatic reactions typically occur in only 1 direction, either because of direct consumption of the product (causing an immediate and continuous equilibrium imbalance) or because of an unfavorable ∆G in the reverse direction.

Is it possible that there is a sort of mass action effect via 17beta-HSD with these androgens having a secondary 17β-hydroxy group that yields a predominance of active andost-1-en-3-ones and androstan-3,17-diols and even 17-beta conjugates that increase net androgen activity and/or good ligands for aromatase? And is this particular to the presence of a secondary 17β-hydroxy group?

I'm going to start (once my mind gets fixated on these questions I just get into it) looking at docking with CYP19A1 and HSD17B1 and some of these metabolites. Do you think SwissADME will be of use?

 

[GuerillaPete]

Is it possible that there is a sort of mass action effect via 17beta-HSD with these androgens having a secondary 17β-hydroxy group that yields a predominance of active andost-1-en-3-ones and androstan-3,17-diols and even 17-beta conjugates that increase net androgen activity and/or good ligands for aromatase? And is this particular to the presence of a secondary 17β-hydroxy group?

I'm going to start (once my mind gets fixated on these questions I just get into it) looking at docking with CYP19A1 and HSD17B1 and some of these metabolites. Do you think SwissADME will be of use?

Confusing right? Why primo is said by some to lower e2 and not by others!
I have run primo for 6 months straight with 450 test.
Dosage of primo was from 400 to 800 and never had low e2 and needed 1 aromasin(25mg) per week to feel good(no bloodwork)
Fast forward 4 months im back on primo.
350 test with 300 primo and im getting low e2 symptoms .
I can make no sense of this primo does have some contributing effect in lowering e2 its just not understood yet !

 

[mattesharpe]

Back in the early 90's I knew top armature bbers and they used real pharm primo came in 3amp boxes 100mg per amp and they would do 2-3 amps per week and they looked great. when it was my time to use aas they stop making it. Although I did use the oral primo 5mg tabs I ran 40mg per day and they use to give me great pumps and blow you up. then they stop the orals in the early 00's.Now leap forward to 2020 and my training partner used so good UGL 300mg per week for 10 weeks and looked like a greek god. Also I trained a fitness chick just this year and had her on 1amp of rimobolan real pharma and she came up a treat. What I am saying is I think all this talk about primo having to be run at 600mg+ per week is a little over kill. I think 300mg is enough to see quality gains just like the guys I knew back in the 90's.

I agree 100% I’m honestly at 300mg a week right now and I haven’t even lifted in a couple days and I’ve lost no muscle and still pretty wide. Even when not getting in all my meals I’ve lost nothing. Primo is the best overall, no need to overdue things. I’ll be running primo forever honestly

 

[GreenAmine]

mass action effect via 17beta-HSD

I believe this would depend on the particular product and how quickly it's consumed in the body, and would therefore vary for each product. It would be a very convoluted system, especially if multiple steroids are stacked together. (This is my way of saying, "That's a great question! I honestly don't know the answer." I'm a physical organic chemist, biochemistry is a hobby.)

As far as the in silico work is concerned, I have never performed any in silico modeling, but SwissADME, from what I've heard, is very good, especially for the price. I'm looking forward to what you find with this.

 

[Khal_T]

Wanna to read and learn more from such articles. They are great and thanks, administer. By the way, stanazolol can the next subject? The water base liquid form and tablet are popular somewhere. But, there is also some confuse for me and someones.

 

[Type-IIx]

Confusing right? Why primo is said by some to lower e2 and not by others!
I have run primo for 6 months straight with 450 test.
Dosage of primo was from 400 to 800 and never had low e2 and needed 1 aromasin(25mg) per week to feel good(no bloodwork)
Fast forward 4 months im back on primo.
350 test with 300 primo and im getting low e2 symptoms .
I can make no sense of this primo does have some contributing effect in lowering e2 its just not understood yet !

Definitely confusing, so much contradiction! My guess is that your E2 is actually elevated (serum), but that Primo acts to reduce estrogen uptake into certain tissues similarly to Mast, and may exert an "anti-E" effect at the target organ level rather than via the suppression of gonadotropin secretion. Semi-educated spitballin'.

 

[GuerillaPete]

Definitely confusing, so much contradiction! My guess is that your E2 is actually elevated (serum), but that Primo acts to reduce estrogen uptake into certain tissues similarly to Mast, and may exert an "anti-E" effect at the target organ level rather than via the suppression of gonadotropin secretion. Semi-educated spitballin'.

I always thought that the aromatase enzyme attaches to the methenolone molecule but it cant aromatize it !
So in return there is less of this enzyme left to aromatize testosterone .
But for me the weird thing is this never happend before and i have experience with the compound.
I did use clomiphene for 6 months before this run and am leaner and on healthy diet, this are the variables .
The solution for me is im gona cruise on test deca and see if it changes things!

 

[Ss99]

So I've been told now repeatedly. There were other compounds involved that likely affect serum E2. If this is the only evidence that exists, mine outweighs it. So far, from the limited data, all I can speculate is that: A) not many guys actually do bloodwork, at least on Primo, and/or B) nobody actually has real Primo.

You can find the Janoshik test reports for the Bayer Test and Primo I sent off earlier this year in my post history and I can send you my on cycle bloodwork too. It reduced my estradiol heavily and has done so for my friends also. I’m no longer signed up to the TrainedByJP site but there were a few pros on there that posted their bloodwork (like JP himself) if I remember correctly and they also saw quite a substantial reduction in serum estradiol. On the other hand I haven’t had any luck with masteron lowering my serum e2 and neither have my friends who have used it too, although I know some coaches like Broderick Chavez claim masteron is very potent at reducing e2 whilst primo is ‘estrogen neutral’, which funnily enough seems to go against the common trend these days.

I think if you look back on Reddit and dig into the weekly bloodwork threads in the steroids subreddit, as well as the compound experience threads, a lot of people have posted their bloodwork showing primobolan lowering their e2 also.

Edit: I see that you mentioned primbolan may reduce the uptake of estrogen into certain tissues but in my experience primobolan seems to be one of the few DHT derivatives that I can run for very long periods of time (I’ve essentially been tapering up and down from it for over 7 months now) without having the what I call ‘pseudo e2’ effects that I seem to have repeatedly with masteron and Anavar when used at high enough dosages. These compounds don’t impact my e2 on bloodwork at all but give me horribly sore joints after a while as well as anxiety, very similar to if I had overdosed on aromasin. I do think masteron has some SERM like effects though even if the research claims otherwise, in my experience and of others I’ve spoken to, the addition of masteron to a cycle will reduce the muscle fullness you get from other compounds (such as high testosterone + estradiol) to some extent, similar to if you had used a SERM like Raloxifene or an AI. I remember coming off of a cycle in which masteron was one of the higher doses drugs being used and looking bigger off cycle than on lol.

I’ve also suspected primobolan had some unique dopaminergic qualities to it for some time and the Swiss Target Prediction seems to somewhat show the potential reasoning behind that.

I’ve also researched primobolan heavily in my spare time and have two studies that mention it’s interaction with estrogen, one being in German and the other in Japanese, although I’ve had trouble translating them even with different sorts of translation apps at my disposal.

 

[GreenAmine]

You can find the Janoshik test reports for the Bayer Test and Primo I sent off earlier this year in my post history and I can send you my on cycle bloodwork too. It reduced my estradiol heavily and has done so for my friends also. I’m no longer signed up to the TrainedByJP site but there were a few pros on there that posted their bloodwork (like JP himself) if I remember correctly and they also saw quite a substantial reduction in serum estradiol. On the other hand I haven’t had any luck with masteron lowering my serum e2 and neither have my friends who have used it too, although I know some coaches like Broderick Chavez claim masteron is very potent at reducing e2 whilst primo is ‘estrogen neutral’, which funnily enough seems to go against the common trend these days.

I think if you look back on Reddit and dig into the weekly bloodwork threads in the steroids subreddit, as well as the compound experience threads, a lot of people have posted their bloodwork showing primobolan lowering their e2 also.

Edit: I see that you mentioned primbolan may reduce the uptake of estrogen into certain tissues but in my experience primobolan seems to be one of the few DHT derivatives that I can run for very long periods of time (I’ve essentially been tapering up and down from it for over 7 months now) without having the what I call ‘pseudo e2’ effects that I seem to have repeatedly with masteron and Anavar when used at high enough dosages. These compounds don’t impact my e2 on bloodwork at all but give me horribly sore joints after a while as well as anxiety, very similar to if I had overdosed on aromasin. I do think masteron has some SERM like effects though even if the research claims otherwise, in my experience and of others I’ve spoken to, the addition of masteron to a cycle will reduce the muscle fullness you get from other compounds (such as high testosterone + estradiol) to some extent, similar to if you had used a SERM like Raloxifene or an AI. I remember coming off of a cycle in which masteron was one of the higher doses drugs being used and looking bigger off cycle than on lol.

I’ve also suspected primobolan had some unique dopaminergic qualities to it for some time and the Swiss Target Prediction seems to somewhat show the potential reasoning behind that.

I’ve also researched primobolan heavily in my spare time and have two studies that mention it’s interaction with estrogen, one being in German and the other in Japanese, although I’ve had trouble translating them even with different sorts of translation apps at my disposal.

Is there any way you can link those 2 studies, or provide the titles? I have a colleague who is Japanese and another who is German, and they will translate them for me. I'm very interested in reading these.

 

[Chael199]

It sucks being dumb. I read thru all this since I last posted. Really lost now, you have to be a chemist to understand the terminology and then a genius to put it all together LOL. I still do the 100mg test c weekly for TRT Dr. But I have tried going up in the 200s and gyno plays a role. Thats why Im looking at Primo and the TRT dose. Just wanting to add some extra to get a little more gains. Would do some Win but dont want to add that stress on the liver and can only tolerate 10 to 15mg a day of it. So Primo seems to be the best for the longer run and help reach my goal which im close to. Well I say close but could be way off I say 10 pounds and would be great on me, but thats alot of muscle and would put me at 165 around 12 to 13 percent BF. So the longer slower run of a easy lower dose compound like Primo I think would add alot of benefits

 

[Ss99]

Is there any way you can link those 2 studies, or provide the titles? I have a colleague who is Japanese and another who is German, and they will translate them for me. I'm very interested in reading these.

Sure, although there’s a high chance these may be the wrong links as I just noted down that they mentioned estrogen or a form of estrogen in them and I’m not kidding when I’ve probably tried to read upwards of 500 of these kind of older studies on different AAS at this point and my note taking skills have always been shit lol

https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/121459/1/18_1111.pdf (I believe I had trouble with this study understanding the figures more than anything else)

[Oxidation of the anabolic substance 1-methyl-androst-1-en-17-beta-o1-3-on by means of hydrogen transfer to estrone. In vitro studies with rat organ slices] - PubMed or the alternative link: OXYDATION DES ANABOLIKUMS 1-METHYL-ANDROST-1-EN-17β-OL-3-ON MIT WASSERSTOFFTRANSFER AUF ÖSTRON

 

[Ironman 580]

It sucks being dumb. I read thru all this since I last posted. Really lost now, you have to be a chemist to understand the terminology and then a genius to put it all together LOL. I still do the 100mg test c weekly for TRT Dr. But I have tried going up in the 200s and gyno plays a role. Thats why Im looking at Primo and the TRT dose. Just wanting to add some extra to get a little more gains. Would do some Win but dont want to add that stress on the liver and can only tolerate 10 to 15mg a day of it. So Primo seems to be the best for the longer run and help reach my goal which im close to. Well I say close but could be way off I say 10 pounds and would be great on me, but thats alot of muscle and would put me at 165 around 12 to 13 percent BF. So the longer slower run of a easy lower dose compound like Primo I think would add alot of benefits

Don’t listen to all these scientific silly posts-the guy posting them prob doesn’t even train or do steroids - just posts all this complicated silly bullshit - I’m tellin u the truth man

 

[GreenAmine]

Don’t listen to all these scientific silly posts-the guy posting them prob doesn’t even train or do steroids - just posts all this complicated silly bullshit - I’m tellin u the truth man

 

[GreenAmine]

It sucks being dumb. I read thru all this since I last posted. Really lost now, you have to be a chemist to understand the terminology and then a genius to put it all together LOL. I still do the 100mg test c weekly for TRT Dr. But I have tried going up in the 200s and gyno plays a role. Thats why Im looking at Primo and the TRT dose. Just wanting to add some extra to get a little more gains. Would do some Win but dont want to add that stress on the liver and can only tolerate 10 to 15mg a day of it. So Primo seems to be the best for the longer run and help reach my goal which im close to. Well I say close but could be way off I say 10 pounds and would be great on me, but thats alot of muscle and would put me at 165 around 12 to 13 percent BF. So the longer slower run of a easy lower dose compound like Primo I think would add alot of benefits

It's not that you're dumb, man, this is simply not your area of expertise. Primo would be a great choice for this purpose, but 165 is really light, unless your height is below average. If you are average height or above, I would suggest eating more and focusing on training before trying to monkey with adding to trt.