Glutamatergic mossy fibers of the hippocampus sprout in temporal lobe epilepsy and establish aberrant synapses on granule cells from which they originate. There is currently no evidence for the activation of kainate receptors (KARs) at recurrent mossy fiber synapses in epileptic animals, despite their important role at control mossy fiber synapses. We report that KARs are involved in ongoing gl...

Although the granule cells of the dentate gyrus are glutamatergic, they contain the machinery for the synthesis and vesiculation of GABA. Furthermore, glutamic acid decarboxylase and the vesicular GABA transporter mRNA are expressed in the granule cells and mossy fibers in an activity-dependent manner, suggesting that these cells release GABA in addition to glutamate. Supporting this hypothesis...

In humans with temporal lobe epilepsy and kainate-treated rats, the mossy fibers of the dentate granule cells send collateral axons into the inner molecular layer. Prior investigations on kainate-treated rats demonstrated that abnormal hilar-evoked events can occasionally be observed in slices with mossy fiber sprouting when gamma-aminobutyric acid-A (GABAA)-mediated inhibition is blocked with ...

Accumulation of abnormally integrated, adult-born, hippocampal dentate granule cells (DGCs) is hypothesized to contribute to the development of temporal lobe epilepsy (TLE). DGCs have long been implicated in TLE, because they regulate excitatory signaling through the hippocampus and exhibit neuroplastic changes during epileptogenesis. Furthermore, DGCs are unusual in that they are continually g...

Posttraumatic epilepsy is a frequent consequence of brain trauma, but relatively little is known about how neuronal circuits are chronically altered after closed head injury. We examined whether local recurrent excitatory synaptic connections form between dentate granule cells in mice 8-12 wk after cortical contusion injury. Mice were monitored for behavioral seizures shortly after brain injury...

Uncaria rhynchophylla (UR), which is a traditional Chinese medicine, has anticonvulsive effect in our previous studies, and the cellular mechanisms behind this are still little known. Because of this, we wanted to determine the importance of the role of UR on kainic acid- (KA-) induced epilepsy. Oral UR for 6 weeks can successfully attenuate the onset of epileptic seizure in animal tests. Hippo...

............................................................................................................... vii Chapter 1: Introduction ........................................................................................ 1 Neurogenesis in the Adult Mammalian Brain ............................................. 1 The Role of Adult Neurogenesis ................................................

Dentate granule cells are generally considered to be relatively resistant to excitotoxicity and have been associated to robust synaptogenesis after neuronal damage. Synaptic reorganization of dentate granule cell axons, the mossy fibers, has been suggested to be relevant for hyperexcitability in human temporal lobe epilepsy and animal models. A recent hypothesis has suggested that mossy fiber s...

Autophagy has been shown to be involved in the pathophysiology of developmental seizure-induced brain damage. The present study aimed to examine whether E-64d, an autophagy inhibitor, was able to facilitate developmental seizure-induced hippocampal mossy fiber sprouting, in particular sprouting-associated zinc transporter signals. Recurrent seizures were induced by penicillin every other day in...