title: Changes in electroencephalographic characteristics and blood-brain barrier permeability in WAG/Rij rats with cortical dysplasia.
abstract: This study investigated the effects of cortical dysplasia (CD) on electrophysiology and blood-brain barrier (BBB) permeability in WAG/Rij rats with genetic absence epilepsy.
  
  
  
  Pregnant WAG/Rij rats were exposed to 145cGy of gamma-irradiation on embryonic day 17 to induce CD. An electroencephalogram was recorded from cortices subdurally in the offspring of the pregnant animals. Horseradish peroxidase (HRP) was used as determinant of BBB permeability.
  
  
  
  A massive tissue loss in the cerebral cortex was seen in WAG/Rij rats with CD (p<0.05). There was a significant decrease in the number and duration of spike-and-wave discharges (SWDs) and an increase in the frequency of SWDs in the WAG/Rij rats with CD when compared with the properties of SWDs in intact WAG/Rij rats (p<0.01). Ultrastructurally, the accumulation of HRP reaction products in the cerebral cortex and thalamus of WAG/Rij rats was significantly higher than that of control values (p<0.01). The accumulation of HRP reaction products in the cerebral cortex and thalamus regions of WAG/Rij rats with CD increased and was higher than that of the control and WAG/Rij animals (p<0.01).
  
  
  
  In our study, we showed that number and duration of SWDs decreased and SWD frequency increased in WAG/Rij rats with CD, suggesting a shift in seizure pattern. The association of these alterations with significant loss of cortical thickness and increased BBB permeability to HRP tracer may represent a causal relation of the EEG abnormalities with cerebral structural changes in these animals.
authors.affiliation: Department of Physiology, Medical Faculty of Kocaeli University, Kocaeli, Turkey.
authors.forename: Deniz
authors.initials: D
authors.lastname: Sahin
authors.affiliation: Department of Laboratory Animals Science, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Canan Ugur
authors.initials: CU
authors.lastname: Yilmaz
authors.affiliation: Department of Neuroscience, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Nurcan
authors.initials: N
authors.lastname: Orhan
authors.affiliation: Department of Forensic Medicine, Istanbul Faculty of Medicine, Istanbul University, Turkey.
authors.forename: Nadir
authors.initials: N
authors.lastname: Arican
authors.affiliation: Koç University School of Medicine, Department of Physiology, Rumelifeneri Yolu, Sarıyer, 34450 Istanbul, Turkey. Electronic address: mehmetkaya@ku.edu.tr.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kaya
authors.affiliation: Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Turkey.
authors.forename: Candan
authors.initials: C
authors.lastname: Gürses
authors.affiliation: Department of Physiology, Medical Faculty of Kocaeli University, Kocaeli, Turkey.
authors.forename: Nurbay
authors.initials: N
authors.lastname: Ates
authors.affiliation: Department of Histology and Embryology, Istanbul Faculty of Medicine, Istanbul University, Turkey.
authors.forename: Bulent
authors.initials: B
authors.lastname: Ahishali
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D002199:Capillary Permeability / Q000502:physiology*; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D004569:Electroencephalography / Q000639:trends*; D005260:Female; D008297:Male; D054220:Malformations of Cortical Development / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*
keywords: Blood-brain barrier; Cortical dysplasia; Electron microscopy; Electrophysiology; Epileptogenesis; WAG/Rij rats