Abstract
This is a mathematical compartmental model of drug pharmacokinetics in the rat brain used to investigate the potential effects of different CSF flow rates on drug pharmacokinetics. Our model implements a local, sustained release approach for drug delivery to the brain. A five-compartment model was designed in MATLAB Simbiology (version R2021a) to simulate drug concentrations in various rat brain compartments over time. The mathematical model utilizes the drug delivery system, interstitial fluid, and cerebrospinal fluid as the primary compartments of interest. An additional compartment was included to simulate the amount of drug that is bound to off-target receptors within the CNS. The final compartment (eliminated) represents the cumulative amount of drug cleared from the CNS or metabolized over the course of the simulation.