Linked Life Data

10902894

Source:http://linkedlifedata.com/resource/pubmed/id/10902894

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-10-25
pubmed:abstractText
In the kainic acid (KA) model of temporal lobe epilepsy, mossy fibers (MFs) are thought to establish recurrent excitatory synaptic contacts onto granule cells. This hypothesis was tested by intracellular labeling of granule cells with biocytin and identifying their synaptic contacts in the dentate molecular layer with electron microscopic (EM) techniques. Twenty-three granule cells from KA-treated animals and 14 granule cells from control rats were examined 2 to 4 months following KA at the light microscopic (LM) level; four cells showing MF sprouting were further characterized at the EM level. Timm staining revealed a time-dependent growth of aberrant MFs into the dentate inner molecular layer. The degree of sprouting was generally (but not invariably) correlated with the severity and frequency of seizures. LM examination of individual biocytin-labeled MF axon collaterals revealed enhanced collateralization and significantly increased numbers of synaptic MF boutons in the hilus compared to controls, as well as aberrant MF growth into the granule cell and molecular layers. EM examination of serially reconstructed, biocytin-labeled MF collaterals in the molecular layer revealed MF boutons that form asymmetrical synapses with dendritic shafts and spines of granule cells, including likely autaptic contacts on parent dendrites of the biocytin-labeled granule cell. These results constitute ultrastructural evidence for newly formed excitatory recurrent circuits, which might provide a structural basis for enhanced excitation and epileptogenesis in the hippocampus of KA-treated rats.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1050-9631
pubmed:author
pubmed:issnType
Print
pubmed:volume
10
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
244-60
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Kainic acid-induced mossy fiber sprouting and synapse formation in the dentate gyrus of rats.
pubmed:affiliation
Department of Neurological Surgery, University of Washington, Seattle 98195-6470, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't