Linked Life Data

9987996

Source:http://linkedlifedata.com/resource/pubmed/id/9987996

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-4-20
pubmed:abstractText
In some children, epilepsy is a catastrophic condition, leading to significant intellectual and behavioral impairment, but little is known about the consequences of recurrent seizures during development. In the present study, we evaluated the effects of 15 daily pentylenetetrazol-induced convulsions in immature rats beginning at postnatal day (P) 1, 10, or 60. In addition, we subjected another group of P10 rats to twice daily seizures for 15 days. Both supragranular and terminal sprouting in the CA3 hippocampal subfield was assessed in Timm-stained sections by using a rating scale and density measurements. Prominent sprouting was seen in the CA3 stratum pyramidale layer in all rats having 15 daily seizures, regardless of the age when seizures began. Based on Timm staining in control P10, P20, and P30 rats, the terminal sprouting in CA3 appears to be new growth of axons and synapses as opposed to a failure of normal regression of synapses. In addition to CA3 terminal sprouting, rats having twice daily seizures had sprouting noted in the dentate supragranular layer, predominately in the inferior blade of the dentate, and had a decreased seizure threshold when compared with controls. Cell counting of dentate granule cells, CA3, CA1, and hilar neurons, with unbiased stereological methods demonstrated no differences from controls in rats with daily seizures beginning at P1 or P10, whereas adult rats with daily seizures had a significant decrease in CA1 neurons. Rats that received twice daily seizures on P10-P25 had an increase in dentate granule cells. This study demonstrates that, like the mature brain, immature animals have neuronal reorganization after recurrent seizures, with mossy fiber sprouting in both the CA3 subfield and supragranular region. In the immature brain, repetitive seizures also result in granule cell neurogenesis without loss of principal neurons. Although the relationship between these morphological changes after seizures during development and subsequent cognitive impairment is not yet clear, our findings indicate that during development recurrent seizures can result in significant alterations in cell number and axonal growth.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9967
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
404
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
537-53
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Mossy fiber sprouting after recurrent seizures during early development in rats.
pubmed:affiliation
Department of Neurology, Harvard Medical School, Children's Hospital, Boston, Massachusetts 02115, USA. holmesg@a1.tch.harvard.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't