Over-expression of P-glycoprotein in malformations of cortical development

Neuroreport. 1999 Nov 8;10(16):3437-41. doi: 10.1097/00001756-199911080-00032.


Drug resistance in epilepsy due to malformations of cortical development (MCD) is unexplained. P-glycoprotein is a mediator of drug resistance, and we propose that MCD lesions over-express P-glycoprotein. Because P-glycoprotein expression may be induced by some antiepileptic drugs (AEDs), we studied brain samples from MCD cases before the onset of seizures or treatment with AEDs. Sixteen MCD cases and 16 age-matched controls were examined using immunohistochemistry. Glial labelling, representing over-expression, was seen in 10 of 16 MCD samples and in two of 16 control samples (p = 0.003). Semiquantitative assessment showed many immunoreactive glia in five of 16 MCD and one of 16 controls. We conclude that there is constitutive over-expression of P-glycoprotein in many MCD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / biosynthesis*
  • Brain Chemistry / physiology*
  • Cell Count
  • Cerebral Cortex / abnormalities*
  • Cerebral Cortex / metabolism
  • Cerebral Cortex / pathology*
  • Child
  • Child, Preschool
  • Epilepsy / metabolism
  • Epilepsy / pathology
  • Humans
  • Immunohistochemistry
  • Infant
  • Infant, Newborn
  • Neuroglia / metabolism


  • ATP Binding Cassette Transporter, Subfamily B