Kaiser
04-10-2007, 05:03 AM
I thought that my partner OTH did such a good write up on this I decided to void copyright from ProM and paste it here. He doesn't like to take credit sometimes for his good work, but I give it to him anyway. Please read as this is what happens pin to receptor:
----------------------
Okay. It’s a dirty job but someone has to do it. Here’s the amazing and wonderful truth regarding what happens from pin to receptor. I think some of the folks here are so misguided that this explanation may be long overdue and might even expose a few myths floating around. It's a good thing for you bastards that I can type 100wpm.
First things first… What are we talking about here? I’m going to describe just what happens to an esterified drug in an oil-based suspension before and after you push down that little plunger.
An ester is just a chemical compound. An ester is formed from a chemical reaction between a carboxylic acid and an alcohol. It’s not necessary to go any deeper than that but suffice it to say, a testosterone ester (or any ester for that matter) is made from the above chemical reaction. Is that enough? So now you have your testosterone ester. Then what? Okay now you have to find a way to get it into your body intact. Well since we’re talking about injectables, I’ll describe that method. Note that you do not have to put testosterone through the process of esterification for it to successfully enter your blood and exhibit its effects. But in many circumstances, drug companies have used oil-based solutions and esters for reasons I'll try to describe. We want to make an injectable form of a drug that works well. More than just that, we also want to increase it’s duration of action, try to maintain higher potency of the injectable solution, and all the while make it so that it’s as painless as possible so that it’s practical to even use at all!
The first thing is, we need to increase the testosterone’s SOLUBILITY so that we can put it into a liquid SOLUTION.. The way we do this most easily is through the esterification process. Usually, the longer the ester (which means the longer the molecular chain), the easier it is to dissolve the compound. Testosterone and many other drugs will not just simply dissolve in water like sugar. One reason we might desire greater solubility (like with a long ester) is so that we can put more of the drug in a smaller amount of oil (or water, or whatever, also known as the SOLVENT) to increase potency. Thus, usually you can create a solution with more mg’s/ml with a long ester than a short one. The other benefit, and perhaps most important, is duration of activity or delivery. It’s the oil that’s the important factor here – not just the ester. The better the ester is dissolved in the oil, the longer it takes to be released. The drug’s soluability in oil is what determines how long it stays in the body. This is also known as the “partition coefficient”.
Let’s summarize this quickly. First you have your drug and then through a chemical reaction, convert it to an ester of the same drug (for example testosterone becomes testosterone undecanoate). You then take the esterified drug (the SOLUTE) and dissolve it in whatever solution you like (the SOLVENT) and pow!!! You have an oil-based testosterone ester SOLUTION. Solute + Solvent = Solution (yes, that’s the oily liquid in the vial or ampule you draw from).
Okay, so now you have your testosterone ester and you want to get the drug (the solution) into your body. You can’t drink it. The hydrochloric acid in your stomach and other enzymes will simply digest the oil and the molecules of testosterone ester along with it. So using a sharp, hollow tube, you insert the oil into a deep part of a muscle. This is where things get a little complicated. Now your ass cheek has a little bubble of oil in deep inside it – we're halfway there now!
After injection into the muscle, the drug remains dissolved in its esterified form in a deposit (in "depot") in the muscle tissue known as a "reservoir". The solution will remain in this reservoir until the blood slowly picks it up. This process isn't very simple either. How can something outside the bloodstream enter the blood stream? Since this is getting long, I'll keep this as short as possible. Your blood and surrounding tissues contain lymph and other fluids. Capillaries are designed so that lymph (and the other fluids) can pass in and out of capillary walls but red blood cells cannot otherwise you'd bleed to death obviously. So again, it's really the ester dissolved in oil and how easily the ester can be "freed" from the oil that determines it's duration of affect (i.e. half-life).
So now the esterified testosterone (the ester) is in your blood. From there, enzymes in your blood, known as "esterase enzymes" break down and cleave off the ester chain from the molecule in a process known as "hydrolization" and then leave the testosterone (or other drug) in its free form to perform its various actions and effects.
Since you want to have steady levels of the drug in your blood, longer esters are usually preferred. Enanthates have 7 carbons and cypionates have 8 carbons. Both will take about 8-10 days to be released fully into the system so shots are best performed every week to 10 days. The more dubious might do injections in half this time in order to have an even steadier blood level although it’s probably unnecessary. This also defeats the purpose of the longer esters as well since the whole purpose is to have LESS frequent injections. I personally feel this whole half-life, more injection stuff, is useless. You’ll just create more scar tissue, use up injection sites, and have higher risk of infection because of the more frequent injections. When taken into consideration, the reasons for doing less injections outweigh, IMO, the small benefit of an increased steady-state plasma concentration. Which if you look at realistically is kind of nonsensical, given the duration of the longer-lasting esters.
So now the released drug (testosterone) is free and is carried along with the rest of your blood (blood is quite a mixture already) until it finds it's way to the receptor sites on your various tissues that will accept it. Sort of like a lock that's awaiting a key. the blood vessels transport all the goodies like oxygen, glucose, peptides, and hormones, through the walls of the capilaries and the cells says HOLY SHIT! I'm getting HUGE!
----------------------
Okay. It’s a dirty job but someone has to do it. Here’s the amazing and wonderful truth regarding what happens from pin to receptor. I think some of the folks here are so misguided that this explanation may be long overdue and might even expose a few myths floating around. It's a good thing for you bastards that I can type 100wpm.
First things first… What are we talking about here? I’m going to describe just what happens to an esterified drug in an oil-based suspension before and after you push down that little plunger.
An ester is just a chemical compound. An ester is formed from a chemical reaction between a carboxylic acid and an alcohol. It’s not necessary to go any deeper than that but suffice it to say, a testosterone ester (or any ester for that matter) is made from the above chemical reaction. Is that enough? So now you have your testosterone ester. Then what? Okay now you have to find a way to get it into your body intact. Well since we’re talking about injectables, I’ll describe that method. Note that you do not have to put testosterone through the process of esterification for it to successfully enter your blood and exhibit its effects. But in many circumstances, drug companies have used oil-based solutions and esters for reasons I'll try to describe. We want to make an injectable form of a drug that works well. More than just that, we also want to increase it’s duration of action, try to maintain higher potency of the injectable solution, and all the while make it so that it’s as painless as possible so that it’s practical to even use at all!
The first thing is, we need to increase the testosterone’s SOLUBILITY so that we can put it into a liquid SOLUTION.. The way we do this most easily is through the esterification process. Usually, the longer the ester (which means the longer the molecular chain), the easier it is to dissolve the compound. Testosterone and many other drugs will not just simply dissolve in water like sugar. One reason we might desire greater solubility (like with a long ester) is so that we can put more of the drug in a smaller amount of oil (or water, or whatever, also known as the SOLVENT) to increase potency. Thus, usually you can create a solution with more mg’s/ml with a long ester than a short one. The other benefit, and perhaps most important, is duration of activity or delivery. It’s the oil that’s the important factor here – not just the ester. The better the ester is dissolved in the oil, the longer it takes to be released. The drug’s soluability in oil is what determines how long it stays in the body. This is also known as the “partition coefficient”.
Let’s summarize this quickly. First you have your drug and then through a chemical reaction, convert it to an ester of the same drug (for example testosterone becomes testosterone undecanoate). You then take the esterified drug (the SOLUTE) and dissolve it in whatever solution you like (the SOLVENT) and pow!!! You have an oil-based testosterone ester SOLUTION. Solute + Solvent = Solution (yes, that’s the oily liquid in the vial or ampule you draw from).
Okay, so now you have your testosterone ester and you want to get the drug (the solution) into your body. You can’t drink it. The hydrochloric acid in your stomach and other enzymes will simply digest the oil and the molecules of testosterone ester along with it. So using a sharp, hollow tube, you insert the oil into a deep part of a muscle. This is where things get a little complicated. Now your ass cheek has a little bubble of oil in deep inside it – we're halfway there now!
After injection into the muscle, the drug remains dissolved in its esterified form in a deposit (in "depot") in the muscle tissue known as a "reservoir". The solution will remain in this reservoir until the blood slowly picks it up. This process isn't very simple either. How can something outside the bloodstream enter the blood stream? Since this is getting long, I'll keep this as short as possible. Your blood and surrounding tissues contain lymph and other fluids. Capillaries are designed so that lymph (and the other fluids) can pass in and out of capillary walls but red blood cells cannot otherwise you'd bleed to death obviously. So again, it's really the ester dissolved in oil and how easily the ester can be "freed" from the oil that determines it's duration of affect (i.e. half-life).
So now the esterified testosterone (the ester) is in your blood. From there, enzymes in your blood, known as "esterase enzymes" break down and cleave off the ester chain from the molecule in a process known as "hydrolization" and then leave the testosterone (or other drug) in its free form to perform its various actions and effects.
Since you want to have steady levels of the drug in your blood, longer esters are usually preferred. Enanthates have 7 carbons and cypionates have 8 carbons. Both will take about 8-10 days to be released fully into the system so shots are best performed every week to 10 days. The more dubious might do injections in half this time in order to have an even steadier blood level although it’s probably unnecessary. This also defeats the purpose of the longer esters as well since the whole purpose is to have LESS frequent injections. I personally feel this whole half-life, more injection stuff, is useless. You’ll just create more scar tissue, use up injection sites, and have higher risk of infection because of the more frequent injections. When taken into consideration, the reasons for doing less injections outweigh, IMO, the small benefit of an increased steady-state plasma concentration. Which if you look at realistically is kind of nonsensical, given the duration of the longer-lasting esters.
So now the released drug (testosterone) is free and is carried along with the rest of your blood (blood is quite a mixture already) until it finds it's way to the receptor sites on your various tissues that will accept it. Sort of like a lock that's awaiting a key. the blood vessels transport all the goodies like oxygen, glucose, peptides, and hormones, through the walls of the capilaries and the cells says HOLY SHIT! I'm getting HUGE!