Figure 6.

CYP drug biotransformation is supported by resorufin and OXC metabolism in EPI‐ECs after GR inhibition. A, Resorufin formation was the highest when using untreated (no MF) EPI‐ECs compared with controls. B, Similar results were obtained when analyzing the abluminal compartment of the DIV‐BBB modules. C, OXC metabolism was increased in noninhibited EPI‐EC compared with EPI‐EC GR‐inhibited and HBMECs. C1, A relative increase in OXC penetration across the BBB was observed when using EPI‐EC GR‐inhibited and HBMECs compared with EPI‐EC non‐inhibited DIV‐BBB. C2, LiCBZ formation in the abluminal side of noninhibited EPI‐ECs, indicating OXC metabolism by a GR‐CYP mechanism. OXC metabolism was lower or negligible in EPI‐ECs after GR inhibition or in HBMECs. D, Levels of resorufin positively correlated with the amount of OXC metabolized. Results are expressed as mean ± SEM. Asterisks indicate P ≤ 0.05