Structural Remodeling of the Neuronal Network in the Dentate Gyrus of the Epileptically Transformed Murine Hippocampus

Immunohistochemical analysis of the hippocampus of a transgene mutant line of the mice (genetic model of temporal epilepsy) demonstrated a progressive increase in the level of brain-derived neurotrophic factor (BDNF) in granular cells of the dentate gyrus and their axons; this increase correlated with an enhancement of the level of epileptic activity. Epileptogenic reprojection of mossy fibers toward an internal zone of the molecular layer of the hippocampus was also observed. In addition, we observed excessive spreading of the zone of axon branching of GABA-ergic basket cells, as compared with the norm; their maximum collateralization was found within an internal zone of the molecular layer of the dentate gyrus. This allows us to hypothesize that the processes of sprouting of the mossy fibers and recovery of recurrent inhibition of the granular cells are interrelated.