Linked Life Data

16289509

Source:http://linkedlifedata.com/resource/pubmed/id/16289509

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2005-11-28
pubmed:abstractText
To clarify the antiepileptic and neuroprotective actions of zonisamide (ZNS), we determined acute effects of ZNS on exocytosis of GABA and glutamate associated with ryanodine-receptor (Ryr) in rat hippocampus using microdialysis. ZNS increased basal GABA release concentration-dependently without affecting basal glutamate release; however, K(+)-evoked glutamate and GABA releases were reduced by ZNS concentration-dependently. Inhibition of Ryr reduced K(+)-evoked GABA and glutamate releases without affecting their basal releases. Ryanodine affected GABA and glutamate releases biphasic concentration-dependently: lower concentration of ryanodine increased both basal and K(+)-evoked releases of GABA and glutamate, whereas higher concentration reduced them. The therapeutically relevant concentration of ZNS inhibited ryanodine-induced GABA and glutamate releases, and abolished the inflection point in concentration-response curve for ryanodine on neurotransmitter exocytosis. These data suggest that ZNS elevates seizure threshold via enhancement of GABAergic transmission during resting stage. ZNS inhibits propagation of epileptic hyperexcitability and Ryr-associated neuronal damage during neuronal hyperexcitable stage. These demonstrations indicate that the indirect inhibition of Ryr activities by ZNS during neuronal hyperexcitability appear to be involved in the mechanisms of action of antiepileptic and neuroprotective actions of ZNS.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0920-1211
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
153-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Effects of zonisamide on neurotransmitter exocytosis associated with ryanodine receptors.
pubmed:affiliation
Department of Neuropsychiatry, Hirosaki University, Hirosaki 036-8562, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't