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Updated: Aug 11, 2026

Setting-up an In Vitro Model of Rat Blood-brain Barrier (BBB): A Focus on BBB Impermeability and Receptor-mediated Transport
Published on: June 28, 2014
[Blood plasma proteins and drug transport across the hemato-encephalic barrier]
Abstract:
The blood-brain barrier being a dynamic membrane interface between the blood and the brain is of great importance for the formation of the pharmacokinetics and pharmacodynamics of neurotropic drugs. One of the main factors influencing diffusion of drugs into the central nervous system is the degree of their binding by plasma proteins. It was supposed that only the unbound fraction of drugs is pharmacologically active. However in some papers the plasma-protein-mediated transport into the rat brain of endogenous compounds and drugs was demonstrated. This indicates that the measuring of the free fraction of a drug in vitro can lead to the underestimation of its concentration in the target organ.
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