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Dear colleagues-
I am using SAAMII to model a two compartment model of peptide PK in
a rat
model using a bolus injection. We take multiple blood samples of 0.2 mls
over 180 minutes and return the red cells thus maintaining blood volume
relatively intact. I am wondering how one corrects for the losses from
the
plasma compartment via sampling alone? The K01 is about .06 pools/min,
and
in the first rapid sampling phase the loss to removed plasma is about .
0025
pools/min or about a 4% error. Since the sampling is not constant the
error
is greater in the first 11 minutes and then rapidly fades as a
contribution.
Any ideas with SAAMII how to model this loss?
Thanks.
Dan
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Dan,
I'm not sure about SAAMII but here's how you do it in acslXtreme:
--
! schedule the sampling events (INITIAL section)
schedule sample .at. 1.0
schedule sample .at. 2.0
schedule sample .at. 5.0
schedule sample .at. 10.0
! DISCRETE sections for adjusting CC conc after a sample
discrete sample
! C = current conc, V = compartment volume
C = C*((V - 0.2)/V) ! vol of draw is 0.2 mls
end
Thanks
Lynne Housand
http://www.acslx.com/ (Gold Standard in PBPK modeling, free for
universities and
now priced at $500 USD for commercial)
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