PD initialization

From: bvatul <bvatul@ufl.edu> Subject: PD initialization Date: Thu, 05 Oct 2000 19:10:51 -0400 Dear NMusers, I am trying to PK/PD model a data set where the PD is explained by an indirect response model with the production of the endogenous substance suppressed by the drug. $DES DADT(1)=-K*A(1) ; PK CP=A(1)/S1 EFF=1-CP/(CP+EC50) DADT(2)=K0*EFF-KE*A(2) ; PD The value of the PD parameter is 10 ng/ml in the absence of the drug. i.e at time zero. In the DV column, I put DV=10 with CMT=2. When we fit the data, why is it that the PD value at time zero starts at zero instead of 10? I looked into page 331 in the help guide. It says that i should initialize the system with a bolus dose into the PD compartment. I dont exactly understand what is intended? Comments/ suggestions are appreciated. Thanks Atul