Linked Life Data

17537977

Source:http://linkedlifedata.com/resource/pubmed/id/17537977

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2007-5-31
pubmed:abstractText
The dentate gyrus filters incoming activity into the hippocampus proper. It plays a role in learning and memory and in pathological states such as epilepsy. Some of hilar interneurons of the dentate gyrus express neuropeptide Y (NPY), which modulates granule cell activity. A subpopulation of the NPY-expressing inhibitory interneurons is sensitive to seizure-induced damage. Pretreatment with beta-estradiol in ovariectomized rats protects hilar interneurons against seizure-induced injury, including the NPY-containing damage-sensitive subpopulation. Here, we demonstrate that beta-estradiol enhances NPY expression within the hilar interneurons. In vitro paired-pulse stimulation of the mixed perforant path revealed beta-estradiol-induced augmentation of granule cell network inhibition, which at interstimulus intervals between 200 and 300 ms (corresponding to approximately 3-5 Hz) was NPY sensitive and involved Y1 receptors, whereas it was insensitive to GABA(B) or metabotropic glutamate receptor antagonists. Additionally, beta-estradiol pretreatment attenuated propagation of low-frequency (3.3 or 5 Hz) burst activity through the dentate gyrus. Scavenging endogenous NPY by intracerebroventricular administration of anti-NPY antibody accelerated kainic acid-induced seizure onset and increased seizure-induced neuronal damage in the hilus compared with rats treated with beta-estradiol alone. Together, we show that beta-estradiol upregulates hilar NPY and that this leads to enhancement in dentate gyrus inhibition of incoming frequencies between 3 and 5 Hz. Such frequencies are similar to the discharge frequencies recorded during seizure initiation in some patients with epilepsy. Thus, beta-estradiol-induced NPY-sensitive filtering of 3-5 Hz frequencies may be an important regulator of incoming seizure activity, but it could also serve a physiological purpose in modulating information flow into the hippocampus proper.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
30
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6054-63
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Beta-estradiol increases dentate gyrus inhibition in female rats via augmentation of hilar neuropeptide Y.
pubmed:affiliation
Saul R. Korey Department of Neurology, Laboratory of Developmental Epilepsy, Albert Einstein College of Medicine and the Einstein/Montefiore Comprehensive Epilepsy Management Center, Bronx, New York 10461, USA. jvelisko@aecom.yu.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural