RE: associatin/dissociation model

From: musor000@optonline.net Subject: RE: [NMusers] associatin/dissociation model Date: Thu, 06 Oct 2005 16:58:24 -0400 Hello Perez, Your advise is really valuable. I ordered the article. We may have reasonable estimates of Kd, but estimates of Koff and Kon look unreliable. I am trying to incorporate Kd and calculate Koff=Kd*Kon. My concerne is that Kd is really small. Can NONMEM handle values such as 10e-10? It cannot read constants if they are too small... KETV is almost the same as KET. I did not do any sensetivity any analysis because I did not design the study. We measure both T (A2) and TV (A4). We do not have V. The model is nonlinear and it is not clear how bioavailability can affect the parameters. Hopefully VD will "absorb" bioavailability as it happens in linear models, i.e. I will estimate VD/Bioavailability. IV data can be available from another study. I will try to add IV data. One thing I just noticed is that I use amounts, but some terms in the model should be concentrations!!! Thank you! Pavel