Original Paper

Anatomic and Electrophysiologic Evidence for a Proconvulsive Circuit in the Dentate Gyrus of Reeler Mutant Mice, an Animal Model of Diffuse Cortical Malformation
Peter R. Patrylo, Amy Willingham

Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Ill., USA

Address of Corresponding Author

Dev Neurosci 2007;29:73-83 (DOI: 10.1159/000096212)

  Key Words

• Dentate granule cells
• Mossy fiber reorganization
• Lissencephaly
• Reelin
• Epileptiform activity

  Abstract

Although cortical malformations (CMs) are often associated with epilepsy, the underlying mechanisms are unknown. The reeler mouse is a model of CM with enhanced susceptibility to epileptiform activity, including the in vitro dentate gyrus, a region normally resistant to seizures. In this study, field potential recordings in hippocampal slices and the Timm stain were used to examine mossy fiber distribution in the dentate gyrus. In artificial cerebrospinal fluid containing bicuculline, 100% of reeler slices and 0% of control slices had spontaneous and antidromic evoked prolonged negative field potential shifts that were blocked by glutamate receptor antagonists. Sections from reeler mice, but not controls, exhibited a dark band of Timm's stain at the molecular layer/granule cell layer border. These data reveal that mossy fiber distribution is altered in reeler mice and coincides with the presence of an abnormal proconvulsive glutamatergic circuit.

Copyright © 2007 S. Karger AG, Basel

  Author Contacts

Peter R. Patrylo, PhD
Department of Physiology
Southern Illinois University School of Medicine
Carbondale, IL 62901 (USA)
Tel. +1 618 453 6743, Fax +1 618 453 1517, E-Mail ppatrylo@siumed.edu

  Article Information

Received: January 20, 2006
Accepted: March 24, 2006
Number of Print Pages : 11
Number of Figures : 6, Number of Tables : 0, Number of References : 68