Experimental design.

<p>Rats were randomly divided into sham and 6-hydroxydopamine (6-OHDA) groups (n = 20 per group) which were injected with vehicle or 6-OHDA (10 µg) unilaterally into the SN, respectively. The successfully PD model rats were screened by apomorphine (0.5 mg/kg) two weeks later after unilateral operation. Then primary normal and PD rCMECs were isolated from brain microvessel fragments of sham and PD model rats and contact co-culture with C6 astroglial cells to construct physiological and PD pathological <i>in vitro</i> BBB models, respectively. The transport of FLZ was measured on the physiological and pathological <i>in vitro</i> BBB models in the absence or presence of transporters specific inhibitors.