IGF-1: Media or Receptor Grade Article?

[goose]

I ran IGTROPIN once at the same dose of media grade and got the same results,and saved an arm and a leg.Would like to hear other views,as Ive had a few Enquiries on this.


IGF-1: Media or Receptor Grade?


Can it be both financially and physically beneficial to pay almost twice the price for receptor grade IGF compared to media grade IGF? It can be and it is! On the financial side, while it is up to twice as expensive, better results require less than half as much. For example, if for the same gains I can use 80 mcg of media grade for $.12 per mcg or 20 mcg of receptor grade for $.30 per microgram, the result is $9.60 for each injection of media grade or $6.00 for each injection of receptor grade. That is a huge savings for using a quarter of the product to inject while getting the same results.


However cost is not the only benefit. There has been a lot of speculation on underground boards lately about the merits of receptor grade vs. media grade hLONG R3IGF-1 (herein referred to as L-IGF), with very little science to back up any claims or bantering. This article will focus on the science side of studies and results using both in-lab studies, as well as real world information from top level athletes.

L-IGF is an 83 amino acid analog of human IGF-I comprising the complete human IGF-I sequence with the substitution of an Arginine for the Glutamine at position 3 (hence R³), and a 13 amino acid extension peptide at the N-terminus.

L-IGF binds specifically to type 1 IGF receptors and promotes cell proliferation, as well as increases cell survival. It has been shown to be equivalent to insulin in supporting cell growth and depending on the situation may outperform insulin in viability and protein production. It is engineered to have a higher biological potency than native IGF-I or IGF-II and has several advantages over recombinant insulin, potency being among them. Published research has shown that supplementation of cell cultures with IGF at a much lower concentration results in equivalent or better productivity than supplementation with standard concentrations of insulin. L-IGF is better able to stimulate the Type I IGF receptor and thus induce a higher level of activation of intracellular signaling molecules which are responsible for promoting cell survival by inhibition of apoptosis.

So as a basic premise you can clearly see the advantages between IGF-1 and the LONG™ version of IGF. The chart below (Figure 1) clearly shows the difference in protein synthesis in cell cultures utilizing equivalent grades (receptor) of IGF-1. The use and uptake of the amino structure is significantly different between the two peptides. Unless you have been stuck in the jungle for the last 2 years, you already know that. What we are working on is trying to determine if there really is a difference between receptor grade and media grade L-IGF.


Figure 1


Look at Figure 2. You can clearly see in both studies a fairly significant difference between IGF and L-IGF. But if you look more closely and compare the two charts (F 1,2) you will see a very surprising difference – the % stimulation of protein synthesis in (Figure 1) receptor grade L-IGF is over 400%, while the (Figure 2) media grade is less than 120%. That is an astounding difference. So what does that mean?


Figure 2


Remember your 9th grade biology class? If not here is a real basic understanding of protein synthesis. It is the process whereby DNA encodes for the production of amino acids and proteins. It involves transcription, the synthesis of a protein, where the corresponding RNA molecule is produced by RNA transcription. One strand of the DNA double helix is used as a template by the RNA polymerase to synthesize a messenger RNA (mRNA). This mRNA migrates from the nucleus to the cytoplasm. During this step, mRNA goes through different types of maturation including one called splicing when the non-coding sequences are eliminated. The coding mRNA sequence can be described as a unit of three nucleotides called a codon.

Translation is the RNA directed synthesis of polypeptides. This process requires all three classes of RNA. Although the chemistry of peptide bond formation is relatively simple, the processes leading to the ability to form a peptide bond are exceedingly complex. The template for correct addition of individual amino acids is the mRNA, yet both tRNAs and rRNAs are involved in the process. The tRNAs carry activated amino acids into the ribosome which is composed of rRNA and ribosomal proteins. The ribosome is associated with the mRNA ensuring correct access of activated tRNAs and containing the necessary enzymatic activities to catalyze peptide bond formation.

The chart below is standard in most high school biology text books and may help provide a clearer understanding of the process. While it is quite complex, it is very important to understand that the difference between 400% and 120% is incredibly significant in scientific studies.


Figure 3


But we are not done yet. There are more tests that show a significant difference between receptor grade and media grade. If you look at Figure 4 below for comparison with IGF in Figure 5, we can establish a link between L-IGF having superior binding to cells by RIA. Both tests were performed by radioreceptor assay, which is a variant test of radioimmunoassay, a procedure that follows the basic principle of radioimmunoassay where there is competition between a radioactive and a non-radioactive antigen for a fixed number of specific antibody binding sites.


Figure 4



Figure 5


Receptors for peptide, protein and glycoprotein hormones, and the catecholamines are located on the plasma membranes of their target cells. Preparations of the receptors may be used as specific, high-affinity binding agents for these hormones in assay methodology akin to that for radioimmunoassay. A particular advantage of the radioreceptor assay is that it has a specificity directed towards the biologically active region of the hormone, rather than to some immunologically active region that may have little (or no) involvement in the expression of hormonal activity. In general, there is good correlation between radioreceptor assays and in-vitro bioassays; differences between results from radioreceptor assays and radioimmunoassays are similar to those noted between in-vitro bioassays and radioimmunoassays. The sensitivity of the method is such that normal plasma concentrations of various hormones have been assayed by this technique.

Purity is an oft discussed issue in the grades of L-IGF. Numbers are being thrown around the net about the “purity” of distributors L-IGF, with numbers ranging from 85% to 99%. Obviously the lower the number, the less purity and less bioavailability you will have from your L-IGF. What is needed is to establish some baseline numbers so we have a working model to gauge the efficacy and usefulness of your L-IGF. The only legitimate, legal manufacturer of all forms of IGF, GroPep, lists their media grade L-IGF as >85% and their receptor grade as >95%.

Hold on a minute, I thought XYZ said their media grade is 97%, how can that be? Well, it can’t. The fact is that GroPep is the only licensed manufacturer of IGF and all variant forms (IGF-1, IGF-II, IGFBP, etc), so if your company is trying to tell you that their L-IGF is more pure than the basic standard of receptor at >95%, than you are being sold snake oil. The other concern people have is that most receptor grade is listed at 99% pure, which it most certainly can. If you notice the “greater than” sign, it means that all receptor grade IGF must be more than 95% pure for it to be classified as receptor and each batch is assigned an assay report where the IGF is measured by HPLC and N-terminal sequence analysis for accuracy. They also measure the molecular weight in Daltons by mass spectrometry.

Back to our purity problem, obviously if the manufacturer states that receptor is minimum >95% pure, then we certainly can’t have media grade that is close to that number. Media grade is >85% and can be up to <95% pure, so any other claims or numbers are misleading. Make sure you question any source you choose to purchase from if they are claiming otherwise. Ask to see reports on where they source from and what the assay report shows to verify their claims. Make them back up what they are asking you to spend your hard earned money on.

In conclusion, while both forms of L-IGF will work, and both will perform the same intended task, there is a major difference between the two forms. The difference in purity is a significant number, especially to a scientist. If you were to perform cell culture tests in a lab, the amount of protein synthesis and uptake, which is to include cell proliferation, you would want to use the highest purity available. A difference of more than 1% is not acceptable and can cause results to vary significantly.

Most people have never tried receptor grade L-IGF because it is extremely expensive to purchase in small quantities, and not very many companies have the capital to purchase the amount needed to make it reasonable to retail. I have personally contacted GroPep from my research firm to inquire about bulk purchases of L-IGF receptor grade and I can assure you that if you have enough money to buy in very large quantities, you certainly can market it at very affordable prices to consumers and still have a profit margin to make it worthwhile.

So while most companies selling media grade will claim that no company can sell receptor and it is just re-labeled media, that is certainly not always the case. Of course there are always unscrupulous business men in this industry which is why I recommended you ask for information before you spend your money.

The real question to be answered is, “Is it worth spending the extra money on receptor grade when people get results on media grade?” The answer is a resounding yes! With the bioavailability being a difference of up to +/- 10%, when <1% makes a significant difference in cell culture lab results, then spending the money is not the question, because the money will be less when purchasing receptor grade.

How’s that? Well look at it this way, using hypothetical pricing for both products, if media grade retails for $120 on average and receptor grade retails for $300 on average, both being for a 1000mcg bottle, what is needed is to know the amount of product needed for use, so the cost can be averaged per use.

Media to receptor grade comparisons in lab studies show a difference of 1% can mean the mcg amount utilized can be as much as a 1:4 ratio, being that for every 1 mcg of receptor grade used, you must use 4 mcg of media grade for equivalent results. Since most guys need to use 80-100mcg of media grade per day for noticeable results, that means if you use real receptor grade L-IGF you will only need to use 20-33mcg per day. That is a significant difference at only a 1% difference; remember there is a tolerance difference of +/- 10% by Gropep standards for cell culture standardization.

So now back to the cost issue. If you need on average 80mcg per day of media grade at $120 a bottle, that is $.12 per mcg or $9.60 per use. If you use receptor grade at $300 per bottle, that is $.30 per mcg or $6.00 per use. You save $3.60 per injection using receptor grade, a significant savings. And that is at hypothetical prices, just shop around and do the same math. I have seen media as low as $100 per bottle and receptor as low as $230 per bottle when both are bought in bulk.

It is up to you how you spend your money, but for me I want the most bang for the buck. The above information is current and valid as provided by GroPep and studies found on the NCBI website. Don’t waste anymore of your money.

[plzr8]

good read goose!

been looking for some articles lately comparing the two grades. any idea when this was written?

i have my receptor on hand which is claimed to be 99% purity. i will start it in about 2 weeks...will be running it at 30-40mcg...ill post feedback then

[goose]

good read goose!

been looking for some articles lately comparing the two grades. any idea when this was written?

i have my receptor on hand which is claimed to be 99% purity. i will start it in about 2 weeks...will be running it at 30-40mcg...ill post feedback then

Good luck buddy...Will PM you soon.Just doing some research for you



Lets hope jayhova,dutch fred or redbaron can comment on this.

[plzr8]

Good luck buddy...Will PM you soon.Just doing some research for you



Lets hope jayhova,dutch fred or redbaron can comment on this.

you the man goose!

yah im sure they both will have some good insight, ive briefly discussed it with jay before

[SPIKE]

Thanks for the info Goose. Do you have a link to where you got this from? Only asking to see when it was written and so I can look at the Figures.

I like this topic b/c I'm seeing more and more UG's coming out with "Receptor grade" LR3. Claiming <95% and selling it very cheap. I remember true Gropep Receptor grade being very expensive. Much higher then the listed $300+ per MG so it makes me wonder.

There's a very popular person (which Plzr8 and myself spoke about) that is selling "receptor grade" at a cost cheaper then most other sources sell media grade. I do have to say that I've only heard good things about this LR3 but dont know if I believe it to be pure Receptor grade. I may have to give it a whirl myself before coming to any conclusions but off hand I dont know if I believe it be be that pure, especially at that price.

The above article was very good and quite accurate. I get my best results running 80-100mcg so would like to see the results that receptor grade would offer at half the dosage. The only person I trust these days with LR3 is the only person I know that has Gropep LR3. I know many that get great results with other LR3 but I feel much more comfortable andf have gotten the best results with Gropep LR3.

[goose]

Nice post jay.I know who you get your IGF from,dont worry I`m not the police,LOL.I tried putting the link in but it got edited here.If anybody wants it PM me I will email it.It`s got great graphs too.Could not find a date but I think it`s new around mid 2006.

I spoke to a big player in the states,he said The only company I he would vouch for is PEL. ProPeptides carries it.The search for the perfect body Contuinues.

[SPIKE]

Here are the figures from the first post. In order from left to right as figure 1-4...

[plzr8]

thanks jay, now i dont have to bug goose for the link

[goose]

You see this was the idea I had.If infact this is true and you can get the same results with 40mcg Receptor Grade,the long term side effects could be reduced if you are a constant user, perhaps.

[SPIKE]

Anyone out there run "receptor grade" LR3?

I'll keep an eye out for you plzr8 at the end of the month when you start.

[plzr8]

Anyone out there run "receptor grade" LR3?

I'll keep an eye out for you plzr8 at the end of the month when you start.

last aas inject was this past sunday

starting the lr3 this coming sunday (2/25) @ 40mcg PWO 5x week

ill keep you posted bro, hoping for good things

[fred9]

hey, very nice thread!!
Ive used something from 5 different sources IGF.. they worked all quite well..
I also used last time receptor grade IGF (claim of the source), i thought it worked different then the others..get more pumped after the injection...

Rodge also tried this receptor grade IGF and didn't really liked it, he personally liked two other brands..(which i haven't used yet)

[plzr8]

hey, very nice thread!!
Ive used something from 5 different sources IGF.. they worked all quite well..
I also used last time receptor grade IGF (claim of the source), i thought it worked different then the others..get more pumped after the injection...

Rodge also tried this receptor grade IGF and didn't really liked it, he personally liked two other brands..(which i haven't used yet)

hmm, interesting....yah i know rodge has tried several

im gonna try to post a once a week update (any more frequent would be sorta pointless), and try to give some general comparisons...

i've run media before but only at 50mcg, but regardless, ill compare it to 40mcg of receptor

[rodge]

Rodge also tried this receptor grade IGF and didn't really liked it, he personally liked two other brands..(which i haven't used yet)

i seriuesly have my doubts that it was receptor grade or even igf-1 at all.

i did a hcg test on it, wich it was,nt. but it did,nt lean me ot one bit. i did get a pump. it did'nt drop my bloodsugar level. it increased my appetite and it gave my tremendous cts

the dose used was 50mcg 4 times a week just as i did with igtropin.

for now i'm gonna stick to my favourite brand

-rodge

[goose]

i seriuesly have my doubts that it was receptor grade or even igf-1 at all.

i did a hcg test on it, wich it was,nt. but it did,nt lean me ot one bit. i did get a pump. it did'nt drop my bloodsugar level. it increased my appetite and it gave my tremendous cts

the dose used was 50mcg 4 times a week just as i did with igtropin.

for now i'm gonna stick to my favourite brand

-rodge

Thanks for that post. ``favourite brand`` MR

[rodge]

Thanks for that post. ``favourite brand`` MR

damn, you know me too well

-rodge

[goose]

damn, you know me too well

-rodge

I have inside info on you buddy


Good to see you around tho....

[test74]

This came from ******** by one of their mods. He wrote an article which is this exact one. he also promotes PEL GH and IGF-1. I have taken the PEL IGF-1 LR3 and didnt notice any differnce what so ever and its suppose to be receptor grade. The best results i got from IGF-1 were from a company called Volumineux or something like that and the pumps were out of this world, I believe it was media grade but was the best i used, and cost me a hell of alot less than i paid for the PEL IGF.

[plzr8]

Thanks for that post. ``favourite brand`` MR

lol i had my money or MR too....

MR was the first one i ever used thanks to rodge

[goose]

PLZ8_

Fred had used the IGF you are going to use,lets hope he can give a Synopsis on his experience,on this thread.I tell you what,he is one of a few guys I respect around here,great knowledge and Expereince and a zeal to experiment,a harcore dude.

[rodge]

PLZ8_I tell you what,he is one of a few guys I respect around here,great knowledge and Expereince and a zeal to experiment,a harcore dude.

i'll second this. very knowledgeable and nice bro.

-rodge

[fred9]

thnx goose+rodge..really apreciate the kind words..

besides Rodge another person overhere in Holland used the IGF..was his first time he used the igf....he injected 50mcg EOD in his legs....he had really very good results with it, he also get some of those growth pain/cramp..just like in puberty when you grow...

ive used 100mcg ED and liked it...but i get big time insomnia..couldnt sleep at all at night..after i stopped the igf i could sleep very good again...quite strange...
injected alway one hour before the workout for the pump...and 15minutes after workout...50mcg each....normally i train around 18-20h so maybe thats the reason why i couldnt sleep at all..
during the igf cycle my strength went up a little and i think i also lost a little bit of fat..

the next stop is MR IGF

[rodge]

ive used 100mcg ED and liked it...but i get big time insomnia..couldnt sleep at all at night..after i stopped the igf i could sleep very good again...quite strange...

thats something i noticed too but this never happened to me when on other (media grade) lr3 igf-1.

-rodge

[goose]

thnx goose+rodge..really apreciate the kind words..

besides Rodge another person overhere in Holland used the IGF..was his first time he used the igf....he injected 50mcg EOD in his legs....he had really very good results with it, he also get some of those growth pain/cramp..just like in puberty when you grow...

ive used 100mcg ED and liked it...but i get big time insomnia..couldnt sleep at all at night..after i stopped the igf i could sleep very good again...quite strange...
injected alway one hour before the workout for the pump...and 15minutes after workout...50mcg each....normally i train around 18-20h so maybe thats the reason why i couldnt sleep at all..
during the igf cycle my strength went up a little and i think i also lost a little bit of fat..

the next stop is MR IGF

Interesting stuff,never had these symptoms your talking about,but I discovered the half-life (approximally) is longer what people think,and one shot is only needed with IGF PWO.It was infact with MR that I attempted to see if you could gain LBM from IGF (very high doses),I got a bizare sides that was scary and erotic,in the morning when I got up I would feel signs of hypo,my last shot was the night before.

[plzr8]

Interesting stuff,never had these symptoms your talking about,but I discovered the half-life (approximally) is longer what people think,and one shot is only needed with IGF PWO.It was infact with MR that I attempted to see if you could gain LBM from IGF (very high doses),I got a bizare sides that was scary and erotic,in the morning when I got up I would feel signs of hypo,my last shot was the night before.

with the extended half-life of IGF in the LR3 version, couldn't there be some benefit of injecting immediately BEFORE starting your workout?

this way you have the igf floating around as your muscles are being worked the hardest for the following hour or so during your workout?

i have alway shot post workout, but just wondered about this...

[goose]

Ok just got a email from a mate so will paste it here.He has another view:

When they say pharmaceutical grade, I believe that's their way of saying media grade. The price you mention breaks down to $260/1,000mcg... which is pretty much the going price for media grade, when you also factor in the insurance and shipping costs.

Receptor grade is generally going to cost 10x more than media grade. I don't personally know anyone who has used genuine receptor grade. The products coming out of South America and China are knock offs and from what I have seen, researched and been told, are all media grade... despite what some salesman or piece of paper says.

True receptor grade is available from the originator and patent holder, Gropep. I wouldn't get it from anyone else.


My understanding is there isn't much, if any, of a difference in effects. A human user could probably never tell which one they were taking. The difference would be noticable to scientists conducting lab experiments using objective measures.

Gropep is the company which originally engineered and patented IGF-1LR3. The following is from their website. You'll notice the difference between media and receptor is in the purity, which is >85% and >95% respectively.


__________________________________________________ _____________
Human LONG™R³IGF-I (Media Grade)
Description:
GroPep scientists have produced Media Grade human LONG™R³IGF-I to provide an inexpensive yet high quality potent IGF-I analog for use as a growth factor supplement for serum-free or reduced-serum culture media. GroPep scientists have engineered this analog with the express purpose of increasing the biological activity of the IGF-I molecule. LONG™R³IGF-I is significantly more potent than human IGF-I in vitro. The enhanced potency is due to decreased binding of LONG™R³IGF-I to IGF binding proteins which normally inhibit the biological actions of IGFs.

LONG is a trade mark owned by GroPep Limited

LONG™R³IGF-I is covered by the following patents assigned to GroPep:
US patent 5,330,971; European patent 429,586; Japanese patent 2,682,738; Australian patent 633,099; Canadian patent 2,033,176

Purity:
> 85 % (by HPLC)
Molecular Weight:
9110 +/- 2 daltons – confirmed by Mass Spectrometry
N-terminal sequence analysis:
18 residues > 95 % single sequence


Human LONG™R³IGF-I (Receptor Grade)
Description:
Human LONG™R³ Insulin -like Growth Factor-I (IGF-I) is an 83 amino acid analog of human IGF-I comprising the complete human IGF-I sequence with the substitution of an Arg for the Glu at position 3 (hence R³), and a 13 amino acid extension peptide at the N-terminus. GroPep scientists have engineered this analog with the express purpose of increasing biological activity. Human LONG™R³IGF-I is significantly more potent than human IGF-I in vitro. The enhanced potency is due to the markedly decreased binding of human LONG™R³IGF-I to IGF binding proteins which normally inhibit the biological actions of IGFs.

LONG is a trade mark owned by GroPep Limited

LONG™R³IGF-I is covered by the following patents assigned to GroPep:
US patent 5,330,971; European patent 429,586; Japanese patent 2,682,738; Australian patent 633,099; Canadian patent 2,033,176;

Purity:
>95 % (by HPLC and N-terminal sequence analysis)
Molecular Weight:
9111 daltons – confirmed by Mass Spectrometry
N-terminal sequence analysis:
18 residues > 95 % single sequence
__________________

[goose]

with the extended half-life of IGF in the LR3 version, couldn't there be some benefit of injecting immediately BEFORE starting your workout?

this way you have the igf floating around as your muscles are being worked the hardest for the following hour or so during your workout?

i have alway shot post workout, but just wondered about this...

I tell what would happen,result wise you would get the same.I have tried this for 5 days and quit as I was on cycle,I injected an hour before Training,you get a multiplied intence pump,I felt it was not needed for me.You could argue it is Beneficial if it gets you other rep or so.I train HIT,so I dont need this extra help,as I rest my body at least 30 hours.IGF will do what slin does to some extend around 50%,so I like the idea of Utilizing the PWO process of recovery with Histidine,Alpha Ketoglutarate and L Ornithine HCL and some other nasty stuff....

[SPIKE]

couldn't there be some benefit of injecting immediately BEFORE starting your workout?

multiplied intence pump

That above is about the only added benefit I could see, Goose hit it all right square on the head.

I tried Pre w/o once and another time pre and post. As goose, my end results were similar to just 1 injection PWO.

The only problem I could see with pre w/o would be for the small portion of people that suffer from hypo type symptoms. They could really run into some serious problems injeciting pre w/o b/c they could be lowering their BS way too low while depleting glucose throughout their workout. Very easy to confuse going hypo with heat exhaustion or simply thinking that you're training really hard. One can drop at any time.

I woudlnt recommend pre w/o to many unless they are strictly looking for some motivation and added pump in the gym and have ran LR3 a few times before. I'd prefer to recommend PWO and use yourself motivation to get you "pumped" in the gym. Believe it or not some of those pre w/o injects pumps were actually painful and didnt allow me to completey finish my workouts.

[SPIKE]

I discovered the half-life (approximally) is longer what people think

For those wondering what you're talking about Goose, here's some info to back up what you're saying:
http://www.igf1-long-r3.com/about.html

The above link completely debunks what most people thought about the board proclaimed 6-8 hour half-life.

Gsxxr actually hooked me up with that link a while ago. Thanks buddy..

[plzr8]

Believe it or not some of those pre w/o injects pumps were actually painful and didnt allow me to completey finish my workouts.

thanks jay for the insight & experience

yah ive always noticed serious pumps when injecting PWO....i can see how they could be intensified and possibly troublesome if done pre-workout

i dont want to throw too many variables into this upcoming run with "receptor" so i can have a somewhat valid comparison, but maybe around week 4 ill try some pre-injects