New onset epilepsy and seizures are common neurological disorders in aged people, second only to stroke and dementia. They are frequently related to other pathological conditions including stroke, trauma, tumors and neurological diseases whereas in about one-third of cases the origin is unknown. Besides the origin, the cellular and molecular events that suddenly trigger seizures are poorly defined. Using an acute model of seizure generation that better resembles new onset seizures, we studied GABAergic interneurons and astrocytes during seizure generation. We found that seizures are preceded by a GABAergic rhythmic hyperactivity that synchronizes pyramidal neurons by inducing a rebound spiking that favors seizures’ onset. Furthermore, the intense activity in GABAergic interneurons evokes Ca2+ elevations in astrocytes that, by releasing glutamate, further excite neuronal network. Elucidating the cellular and molecular events that generate seizures may reveal new targets for treatment of new onset seizures and epilepsy.
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This work was supported by the National Research Council of Italy (CNR), Research Project “Aging: molecular and technological innovations for improving the health of the elderly population” (Prot. MIUR 2867 25.11.2011).
Compliance with ethical standards
Conflict of interest
On behalf of all authors, the corresponding authors declare that there is no conflict of interest.
Statement of human and animal rights
All procedures performed in the original studies described in this contribution were in accordance with the ethical standards of the institutional research committee (Ethical approval by the Ethical Committee of both the University of Padova and the Italian Ministry of Education, University and Research).
No human participant was included in the studies described in this contribution.
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