Linked Life Data

21112087

Source:http://linkedlifedata.com/resource/pubmed/id/21112087

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-1-10
pubmed:abstractText
The factors that influence Leydig cell activity currently include peptides such as neuropeptide Y (NPY). In this work we investigated the ability of this compound, injected directly into the testes of adult male rats, to alter testosterone (T) release into the general circulation. At a 5?g/kg dose administered 1h prior to challenge with human chorionic gonadotropin (hCG, 1.0 U/kg, iv), NPY significantly (P<0.01) blunted the T response to this gonadotropin. The inhibitory effect of NPY was observed in animals pretreated with an antagonist to gonadotropin-releasing hormone or not, indicating that the decrease in plasma T found was most likely independent of pituitary luteinizing hormone. However, testicular levels of steroidogenic acute regulatory (STAR) protein or translocator protein (TSPO) in the Leydig cells did not exhibit consistent changes, which suggested that other mechanisms mediated the blunted T response to hCG. We therefore used autoradiography and immunohistochemistry methodologies to identify NPY receptors in the testes, and found them primarily located on blood vessels. Competition studies further identified these receptors as being Y(1), a subtype previously reported to modulate the vasoconstrictor effect of NPY. The absence of significant changes in STAR and TSPO levels, as well as the absence of Y(1) receptors on Leydig cells, suggest that NPY-induced decreases in T release is unlikely to represent a direct effect of NPY on these cells. Rather, the very high expression levels of Y(1) found in testicular vessels supports the concept that NPY may alter gonadal activity, at least in part, through local vascular impairment of gonadotropin delivery to, and/or blunted T secretion from, Leydig cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1532-2785
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
55-61
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Neuropeptide Y acts within the rat testis to inhibit testosterone secretion.
pubmed:affiliation
The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute for Biological Studies, La Jolla, CA 92037, United States.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't