Barbituate versus benzodiazapine potency

[serotonin2A]

OK, but going back to the percentages: 50% are already occupied by sero and the addition of gepi at its Ki should occupy 50% of the remaining 50% that are not occupied by sero (like you said, gepi can't "drag" sero off the sites), so therefore the total occupancy should be 50% sero + 50% x 50% gepi = 75%, so why did you say it's 66% (I know that you are right and I'm wrong, because this specific receptor theory stuff isn'T my specialty, i just wanna know why 75% is wrong)

Serotonin will eventually start to dissociate, and then serotonin and gepirone binding will reach an equilibrium (at which point there will be 66% occupation).

Note that this is an imaginary example where serotonin and gepirone have exactly the same binding affinity.

 

[WSH]

Serotonin will eventually start to dissociate, and then serotonin and gepirone binding will reach an equilibrium (at which point there will be 66% occupation).

Note that this is an imaginary example where serotonin and gepirone have exactly the same binding affinity.

Thank you i think now i understand.

And the 66% comes from the occupancy formula right?
2 / (2 + 1) = ~66%

So if a third partial agonist, let's say buspirone (which also has exactly the same binding affinity in our little ivory tower ) was added at its Ki, then the total occupancy of all three woud be 3 / (3 + 1) = 75%, right?