Linked Life Data

9325355

Source:http://linkedlifedata.com/resource/pubmed/id/9325355

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1997-11-13
pubmed:abstractText
Temporal lobe epilepsy is associated with a characteristic pattern of synaptic reorganization in the hippocampal formation, consisting of neuronal loss and aberrant growth of mossy fiber collaterals into the dentate gyrus inner molecular layer. We have used the rat pilocarpine model of temporal lobe epilepsy to study the functional consequences of mossy fiber sprouting on excitatory activity and kappa-opioid receptor-mediated inhibition. Using the whole cell voltage-clamp technique, we found that abnormal excitatory activity was evident in granule cells of the dentate gyrus from pilocarpine-treated rats. The frequency of spontaneous excitatory postsynaptic currents (EPSCs) was increased greatly in cells from tissue in which significant mossy fiber sprouting had developed. In the presence of bicuculline, giant spontaneous EPSCs, with large amplitudes and long durations, were seen only in association with mossy fiber sprouting. Giant EPSCs also could be evoked by low-intensity stimulation of the perforant path. Mossy fibers release not only excitatory amino acids, but also opioid peptides. kappa-Opioid receptor-mediated inhibition in normal Sprague-Dawley rats was seen only in hippocampal sections from the ventral pole. In pilocarpine-treated rats, however, kappa receptor-mediated effects were seen in both ventral and more dorsal sections. Thus in this model of temporal lobe epilepsy, several types of abnormal excitatory activity were observed, thereby supporting the idea that mossy fiber sprouting leads to recurrent excitatory connections. At the same time, inhibition of excitatory activity by kappa-opioid receptors was increased, perhaps representing an endogenous anticonvulsant mechanism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1860-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Spontaneous excitatory currents and kappa-opioid receptor inhibition in dentate gyrus are increased in the rat pilocarpine model of temporal lobe epilepsy.
pubmed:affiliation
Department of Pharmacology, University of Washington, Seattle, Washington 98195-7280, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't