RT Journal Article
SR Electronic
T1 Recurrent Mossy Fibers Establish Aberrant Kainate Receptor-Operated Synapses on Granule Cells from Epileptic Rats
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 8229
OP 8239
DO 10.1523/JNEUROSCI.1469-05.2005
VO 25
IS 36
A1 Epsztein, Jérôme
A1 Represa, Alfonso
A1 Jorquera, Isabel
A1 Ben-Ari, Yehezkel
A1 Crépel, Valérie
YR 2005
UL http://www.jneurosci.org/content/25/36/8229.abstract
AB 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 glutamatergic transmission in granule cells from chronic epileptic but not control animals. KARs provide a substantial component of glutamatergic activity, because they support half of the non-NMDA receptor-mediated excitatory drive in these cells. KAR-mediated EPSCKAs are selectively generated by recurrent mossy fiber inputs and have a slower kinetics than EPSCAMPA. Therefore, in addition to axonal rewiring, sprouting of mossy fibers induces a shift in the nature of glutamatergic transmission in granule cells that may contribute to the physiopathology of the dentate gyrus in epileptic animals.