While reading this article keep in mind that Tren (trenbolone finaplix) binds to
the androgen receptor incredibly well.
The Androgen Receptor
There are many mechanisms behind the ability of androgens to reduce body fat.
However, one key determinant of the amount of adipose tissue reduced is that
particular androgen's ability to bind to the AR.
I need to mention that most androgens interact with both AR and GR (Glucocorticoid
Receptors). We'll touch on that later. For now, let me explain why it matters
how well an androgen binds to the AR in terms of reducing adipose tissue. Most
of you know that ARs are present in tissue such as muscle. This is one of the
mechanisms behind their ability to induce muscular hypertrophy. Now what does
this have to do with body fat? Simple, AR's are present in adipose tissue as
well. (1)
What does this mean? Well, it's been shown that the higher the density of ARs,
the more that lipid uptake is inhibited. (2) It's also been shown that androgens
that bind avidly to the AR cause an increase or upregulation of AR in adipocytes.
(1) I think the greater the androgen binds to the AR, the more upregulation of
AR in adipocytes occurs. This would lead to a significant reduction in
subcutaneous adipose tissue. (3)
Notice that I specifically mentioned subcutaneous adipose tissue (fat right
beneath the skin) and not visceral adipose tissue (fat around the internal
organs). Why did I bother to differentiate between the two? Simple. For the most
part, we bodybuilders are concerned only with subcutaneous adipose tissue.
Visceral fat doesn't have much of an effect on a person's appearance. For that
reason, we're only concerning ourselves with subcutaneous adipose tissue.
Now, what other mechanisms of action can account for the effects seen with those
steroids that bind tightly to the AR? Well, those that bind tightly to the AR
will decrease LPL (Lipoprotein Lipase), which is an enzyme that causes lipid
accumulation. (4) They may also decrease Acetyl-CoA Carboxylase and Fatty Acid
Synthetase.(5)
Another interesting note is that androgens have been shown to increase adenyl
cylclase as well. This is the enzyme which is responsible for the conversion of
cytoplasmic ATP into cyclic AMP. Increasing its concentrations is a good thing,
in other words.
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