Efflux transport systems for drugs at the blood-brain barrier and blood-cerebrospinal fluid barrier (Part 2)

Penetration of the blood-brain barrier or blood-cerebrospinal fluid barrier is necessary if a drug is to achieve the required concentration for a desired pharmacological effect. Efflux transport systems at such barriers provide protection for the CNS by removing drugs from the brain or cerebrospinal fluid, and transferring them to the systemic circulation. In Part 2 of this review, in vivo and in vitro studies of efflux transport via these barriers are discussed, with reference to the transporters previously described in Part 1(1).