Linked Life Data

15084640

Source:http://linkedlifedata.com/resource/pubmed/id/15084640

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-8-27
pubmed:abstractText
Formation of local excitatory circuits may contribute to epileptogenesis. We tested the hypothesis that epileptogenesis is associated with increased recurrent excitation in the hippocampal CA1 area of rats with kainate-induced epilepsy. Whole cell recordings were obtained during focal flash photolysis of caged glutamate, which served as a focal excitant to activate local pyramidal cells and to study possible connections between neurons. Kainate-treated rats with spontaneous seizures were studied months after status epilepticus and were compared with saline-injected control rats. Experiments were done in isolated CA1 minislices and in bicuculline to block GABA(A) receptors. Spontaneous excitatory postsynaptic currents (sEPSCs) were present in 42% of the CA1 pyramidal cells from controls and 62% from kainate-treated rats. The frequency of sEPSCs in the kainate group was significantly higher than that in the control group, but mean amplitude was not different. Flash photolysis of caged glutamate on the somatodendritic area of CA1 pyramidal neurons caused a burst of action potentials. Local excitatory connections between CA1 pyramidal cells were found in 4 of 48 neurons (8%) in slices from control animals, but in significantly more neurons (12 of 37; 32%) from rats with kainate-induced epilepsy exhibited interconnections (P < 0.001). Photoactivation of glutamate on recorded CA1 pyramidal cells in the kainate group sometimes caused afterdischarges, but not in controls. The kainate-treated rats with pyramidal cells that responded to photostimulaltion with repetitive EPSCs appeared to have experienced more severe seizures. These data provide new electrophysiological evidence for the formation of recurrent excitatory circuits in the CA1 area of rats with kainate-induced epilepsy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
92
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1366-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Increased excitatory synaptic activity and local connectivity of hippocampal CA1 pyramidal cells in rats with kainate-induced epilepsy.
pubmed:affiliation
Dept. of Biomedical Sciences, Anatomy and Neurobiology Section, 1617 Campus Delivery, Colorado State University, Fort Collins, CO 80523, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.