Please Explain "steroid receptors"

**hardgainer1** · 03-21-2007, 08:52 AM

What is it that people mean when they say you have to come off because your "receptors" are saturated which makes you stop responding to androgens. Is this just "bro lore" or a real thing that happens when you use aas with out taking long enough breaks inbetween cycles.

**Knoxston** · 03-21-2007, 09:14 AM

sounds like it makes sense to me but dont know if its true or just a myth

**jagdpanther** · 03-21-2007, 09:22 AM

This is a post by musclescience that is interesting.

Food for thought, long read but great question to think about

I'm still trying to get more details but as I understand it the AR receptors neither decrease in number nor do they become saturated, rather due to a change in thier confirmation (shape), which also effects areas of electrical charge, they become less efficient. Less efficient translates in to not binding as frequenlty or as strongly to the steriod . A pausible effect of not binding as strongly is that the A.R.-steriod complex won't make it to the chromoses before coming apart where it would otherwise initiate transcription of DNA for protien synthesis.

If any real science guys want to correct me please do.

**hardgainer1** · 03-21-2007, 09:47 AM

hmm very interesting

**taiboxa** · 03-21-2007, 10:13 AM

If you really wanna get down to it.. read this lol
How long for receptors to clear?
have fun, btw its an awsome thread and i was going to bump it again but didnt know if u would actually see it

**jagdpanther** · 03-21-2007, 10:28 AM

Excellent addition to the topic Taiboxa (I haven't read all of it yet but got through the first page). SHBG certainly does come into play as well. This is another topic that is still in debte. I've seen and will try to find some studies on both sides of the coin. One study I recalled showed that SHGB actually dropped while on cycle (I think short duration of cycle had something to do with this) while another study conducted on women showed that after being on the pill for a year+ the level of SHBG was highly elevated and stayed that way for over a year after coming off the pill. I know some people will highly argue the fact the second study was on women but i think it should still be introduced.

**jagdpanther** · 03-21-2007, 10:41 AM

Here be the study on birth control, elevated estrogen, and women.
http://www.blackwell-synergy.com/doi...9.2005.00198.x

Maybe something to think about for those who let estrogen go wild while on cycle. Then again another valid study shows SHGB go down while on cycle. let me see if I can find that one(that will be later as work is getting in the way of this important stuff).

**jagdpanther** · 03-21-2007, 05:04 PM

This is not thestudy I was looking for but its what I found for now.
If you want to cut to the chase and I haven't read all of this go to page 4
and read the section on Laboratory studies.
after edit opps I realized iforgot the link, aren't I an idiot

http://www.aace.com/pub/pdf/guidelines/hypogonadism.pdf

Low testosterone levels and elevated estradiol increase the production of SHBG. From what I gather the body tries to produce more SHBG when you have low test because it is trying to raise total test levels including that bound by the SHBG. This is not enough proof for me to say that high levels of test would decrease SHBG but I know the study is out there. The peice above though helps me understand the why.

As for increased estradiol it clearly increases SHBG - and this makes a very strong reason for the use of AIs not just SERMs while on cycle(especially for Dbol users).

**Pooks** · 03-21-2007, 06:02 PM

So higher SHBG (sex hormone-binding globulin) is a good thing?

I found this, I don't think i understand what it means:

"Numerous studies have shown that total testosterone (free+SHBG bound+albumin bound) correlates with SHBG levels. As SHBG levels rise, testosterone is believed to partition out of the free and albumin bound phases into the SHBG phase. Testosterone bound tightly to SHBG is less subject to the action of metabolic enzymes. Hence the increase in SHBG bound testosterone leads to a decrease in the metabolic clearance rate of testosterone, with a corresponding increase in total plasma testosterone."

http://www.digitalnaturopath.com/cond/C654345.html <--- the source of it.

Melatonin also keeps popping up a lot when I research it.
It has something to do with the Receptors and all that.
but still trying to figure out if its a good thing to be taking during a cycle or bad one.

**MuscleScience** · 03-21-2007, 09:19 PM

bound test and free test are at equilibrum with each other in blood plasma. Bound test is considered not to be metabolically significant. Its only unbound test that goes into cells and causes a responce.

**Pooks** · 03-21-2007, 09:35 PM

Originally Posted by MuscleScience

bound test and free test are at equilibrum with each other in blood plasma. Bound test is considered not to be metabolically significant. Its only unbound test that goes into cells and causes a responce.

so we want the unbound test, as much as possible.. meaning low SHBG levels are desired?

**jagdpanther** · 03-21-2007, 09:35 PM

Hey pook,

So higher SHBG (sex hormone-binding globulin) is a good thing?

No I definaletly think to much SHGB is a bad thing as far as testosterone and muscle enhancement goes.

I read that quote earlier today as well.. trying to remember where. It wasn't from the link you put either up.

I think the last sentence of the quote is key
"Hence the increase in SHBG bound testosterone leads to a decrease in the metabolic clearance rate of testosterone, with a corresponding increase in total plasma testosterone".

SHGB keeps it from being bio available to build muscle orbe used up. When your quote is read with the following in mind from my previous link it makes more sense.

"Although a testosterone determination is the threshold
test in the evaluation of suspected male hypogonadism, the
total testosterone concentration may be within the normal
range in men with primary testicular disorders such as
Klinefelter’s syndrome. Low production of testosterone
and increased estradiol stimulate production of SHBG by
the liver. The increased level of SHBG results in higher
circulating total testosterone than would otherwise be
present with low circulating free testosterone."

I am readin into this a bit but it seems that the male body is sensative to the total level of testosterone. If the body realizes that total test is low it produces more SHGB to keep the test from being used by the body - hence making total test appear normal while free test and/or albumin bound test is low. In this case elevated shbg is masking the low test levels by making total test appear normal.

As fitness people we are interested in the free test and the albumin bound test. The binding between albumin and test is relatively weak when compared to SHBG, thus it offers some protection and helps shuttle test to different areas of the body but the bond is weak enough that it can let the test go under the right conditions to allow the test to be used.

As for melatonin I'm not sure I've taken it to help me sleep before -i'll try and read upon it.

If I've done a poor job on explaining myself or someone disagrees with what I'm proposing, please call me on it as this is a learning process for me. If I'm wrong, I'm happy to admit it, if I'm right hopefully the discussion will be of benefit to everyone including me by forcing me to improve my understanding and ability to regugetate it.

**jagdpanther** · 03-21-2007, 10:03 PM

Originally Posted by taiboxa

If you really wanna get down to it.. read this lol
How long for receptors to clear?
have fun, btw its an awsome thread and i was going to bump it again but didnt know if u would actually see it

Damn that is a good thread the more I read it the better it gets.

Pooks -I'll modify my previous statement as it seems like there are arguements for higher SHBG in PCT (but not during cycle).

**Pooks** · 03-21-2007, 10:06 PM

http://www.digitalnaturopath.com/cond/C655233.html read this too..

u're pretty much on i beleive, it states: "Because SHBG is often low in women with hirsutism, free testosterone is elevated while the total testosterone concentration is normal. This means the free testosterone portion is responsible for increased male characteristics. Just an increase in free testosterone with no increase in total testosterone can produce significant consequences.

Estrogens increase liver manufacture of SHBG. Androgens decrease it. A lack of estrogens can effectively increase available blood androgens."

INCREASED MALE CHARACTERISTICS IN FEMALES WITH LOW SHBG.
ESTROGENS INCREASE IT... ANDROGENS DECREASE IT.

**Pooks** · 03-21-2007, 10:12 PM

I suppose it gets better...

"Low levels of SHBG are consistently linked to high levels of insulin in the body. Sustained high levels of insulin are, in turn, associated with the development of the chronic diseases such as high blood pressure, diabetes and coronary heart disease."

So taking insulin injections like of us do, definitely helps while being on a cycle.

**Pooks** · 03-21-2007, 11:01 PM

Some more stuff:
from here http://edrv.endojournals.org/cgi/content/full/26/6/833

"Biologically, the most important plasma androgen is testosterone . It is largely bound to plasma proteins, only 1–2% being free, 40–50% being loosely bound to albumin, and 50–60% being specifically and strongly bound to the SHBG (8, 9). Unbound testosterone diffuses passively through the cell membranes into the target cell, where it binds to the specific androgen receptor (AR) (10). The serum free testosterone (FT) and the albumin-bound testosterone represent the fractions readily available for biological action."

"There is an age-associated increase of SHBG levels by about 1.2% per year "