Dear nmusers
[transit compartment model in PK/PD modeling]
I was implementing transit model for PK/PD model of ARB(angiotensin II
receptor blocker) effect. I had two questions for this model.
1) How can I use the method of Savic(to account for delay in absorption;
Savic et al, 2007) to account for delay in the effect?
2) If the above mentioned method is not available for the effect model and
the number of compartment should be manually optimized, what is the best
method to determine optimal number of transit compartment?
Sincerely
Jongtae Lee M.D.
Resident
Clinical pharmacology
Seoul St. Mary's hospital
505 Banpo-Dong, Seocho-Gu, Seoul 137-701, Korea
TEL: +82-2-2258-7882 FAX: +82-2-2258-7876
[email protected]
[transit compartment model in PK/PD modeling]
Hi,
The algebraic equation described by Savic and colleagues applies when
the input into the first transit compartment is an instantaneous impulse
(ie bolus or oral dose). As far as I know, there is no algebraic
solution for this kind of systems when the input is not instantaneous.
This seems to be the case for your PKPD analysis as the PK of ARB is a
continuous process over time and not an impulse. You will have to
include the transit compartments as separate equations into your system
of differential equations. Based on the principle of parsimony, I would
optimize the number of compartments by adding one compartment at a time
into the system.
As a starting point, you may want to try simulation in Berkeley Madonna.
It has a array notation that can be used to define arrays of
differential equations and therefore applies very nicely to this kind of
problem.
Sebastien Bihorel
PK/PD Scientist
Cognigen Corporation
(716) 633-3463 ext. 323
이종태 wrote:
>
> Dear nmusers
>
> [transit compartment model in PK/PD modeling]
>
> I was implementing transit model for PK/PD model of ARB(angiotensin II
> receptor blocker) effect. I had two questions for this model.
>
> 1) How can I use the method of Savic(to account for delay in absorption;
> Savic et al, 2007) to account for delay in the effect?
> 2) If the above mentioned method is not available for the effect model and
> the number of compartment should be manually optimized, what is the best
> method to determine optimal number of transit compartment?
>
> Sincerely
>
> *Jongtae Lee M.D.***
>
>
> Resident
>
> Clinical pharmacology
>
> Seoul St. Mary's hospital
> 505 Banpo-Dong, Seocho-Gu, Seoul 137-701, Korea
> TEL: +82-2-2258-7882 FAX: +82-2-2258-7876
>
> [email protected]
>