Seroquel: Doses that change affinity to different receptors

[uponbenzos]

This is kinda a complicated question & maybe should belong in ADD. So sorry mods if i put it in the wrong spot.
I found this info on the internet by googling "seroquel receptor affinity"
http://thelastpsychiatrist.com/2007/07/the_most_important_article_on.html
Basically unlike most drugs seroquel has different effects at different doses. Read the link if u dont know what i mean. If u cant be bothered to read it here's a quote from it:

Instead of thinking that the drug binds to all receptors simultaneously, a better analogy would be a champagne fountain, like at a wedding. Except I hate champagne, so pretend it is a rum fountain. Rum fills the top level, overflows into the second level, then that overflows into the third, etc. You can't get anything into level 3 until you fill levels 1 and 2. And, once you've filled level 1, you can't put anything more into it.

Get it? So level one can be labeled H1, level two is alpha 1, and level 3 is D2. (2)

So you can see that, at some dose, there is no more increasing sedation with Seroquel. You've filled up level 1-- the H1 section. Going from 25mg to 50mg is a big jump in sedation (level 1), but going from 400mg (level 3) to 800mg is not felt to be an increase in sedation. It's the same amount of sedation, because by the time you hit 400mg, you were all full up. (3)

But there’s a dark side to my analogy, and it isn’t the rum fits. Here’s the thing: if one molecule of Seroquel goes to H1, and not to D2, then can it have any antipsychotic effect? No. One molecule binds to H1, so it isn't an antipsychotic, it's an antihistamine.

So it seems it stops blocking histamine making it an antihistamine at any dose.

Approx what dose does it start blocking A1 receptor?
Most importantly, what dose does it start blocking D2 making it an antipsychotic?

Ive spent hrs reading through sites on google & cant get any results. I only know it starts blocking D2 somewhere around 250mg. If someone could prove a source that would be great.