Graphical Evaluation of Blood-to-Brain Transfer Constants from Multiple-Time Uptake Data

A theoretical model of blood–brain exchange is developed and a procedure is derived that can be used for graphing multiple-time tissue uptake data and determining whether a unidirectional transfer process was dominant during part or all of the experimental period. If the graph indicates unidirectionality of uptake, then an influx constant ( K i ) can be calculated. The model is general, assumes linear transfer kinetics, and consists of a...