Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-12-18
pubmed:abstractText
The morphometry of astrocytes in the arcuate nucleus exhibits cyclic changes during the estrous cycle leading to dynamic changes in the communication between neurotransmitters and neuropeptides that regulate pituitary hormone secretion. Data suggest that remodeling of direct and/or indirect inputs into GnRH neurons may influence the timing and/or amplitude of the preovulatory LH surge in young rats. We have previously found that aging alters the timing and amplitude of the LH surge. Therefore, the purpose of this study was to focus on the rostral preoptic area where GnRH cell bodies reside. We assessed the possibility that the morphometry of astrocytes in the rostral preoptic area displays time-related and age-dependent changes on proestrus. Our results demonstrate that, in young rats, astrocyte cell surface area decreases between 0800 h and 1200 h, before the initiation of the LH surge. Changes in surface area over the cycle were specific to astrocytes in close apposition to GnRH neurons. In contrast, in middle-aged rats astrocyte surface area was significantly less than in young rats and did not change during the day. These findings suggest that a loss of astrocyte plasticity could lead to the delayed and attenuated LH surge that has been previously observed in middle-aged rats.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
144
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
274-80
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
The morphometry of astrocytes in the rostral preoptic area exhibits a diurnal rhythm on proestrus: relationship to the luteinizing hormone surge and effects of age.
pubmed:affiliation
Department of Physiology, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0098, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.