These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Repetitive perforant-path stimulation induces epileptiform bursts in minislices of dentate gyrus from rats with kainate-induced epilepsy.
    Author: Shao LR, Dudek FE.
    Journal: J Neurophysiol; 2011 Feb; 105(2):522-7. PubMed ID: 21148094.
    Abstract:
    The epileptic hippocampus has an enhanced propensity for seizure generation, but how spontaneous seizures start is poorly understood. Using whole cell and field-potential recordings, this study explored whether repetitive perforant-path stimulation at physiological frequencies could induce epileptiform bursts in dentate gyrus minislices from rats with kainate-induced epilepsy. Control slices from saline-treated rats responded to single perforant-path stimulation with an excitatory postsynaptic potential (EPSP) and a single population spike in normal medium, and repetitive stimulation at different frequencies (0.1, 1, 2, 5, 10 Hz) did not cause significant increases in the responses. Most minislices (82%) from rats with kainate-induced epilepsy also responded to single perforant-path stimulation with an EPSP and a single population spike/action potential, but some slices (18%) had a more robust response with a prolonged duration and negative DC shift or responses with two to three population spikes. Repetitive perforant-path stimulation at 5-10 Hz, however, transformed the single-spike responses into epileptiform bursts with multiple spikes in half (52%) of the slices, while lower frequency (e.g., ≤ 1 Hz) stimulation failed to produce these changes. The emergence of epileptiform bursts was consistently associated with a negative field-potential DC shift and membrane depolarization. The results suggest that compared with the controls, the "gate" function of the dentate gyrus is compromised in rats with kainate-induced epilepsy, and epileptiform bursts (but not full-length seizure events) can be induced in minislices by repetitive synaptic stimulation at physiological frequencies in the range of hippocampal theta rhythm (i.e., 5-10 Hz).
    [Abstract] [Full Text] [Related] [New Search]