ABCB1 and cerebral cortical dysplasia: In this study it was shown that phenytoin was significantly lower in astrocytes from epileptic tissue than in control astrocytes.[90] In a recent study, the normal brain showed no expression of MDR1 in the neurons or astrocytes while intense overexpression of MDR1 and MRP1was demonstrated in the neurons and the reactive astrocytes in the dysplastic tissues that were resected from patients with focal cortical dysplasia.[91]