Linked Life Data

9751509

Source:http://linkedlifedata.com/resource/pubmed/id/9751509

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1998-10-8
pubmed:abstractText
Retinoid X receptors (RXRs) are key regulators in retinoid signaling. Knowledge about the effects of 9-cis-retinoic acid (9-cis-RA), the natural ligand for the RXRs, may also provide insight in the functions of RXRs. In this study, the effect of 9-cis-RA on spermatogenesis in vitamin A-deficient (VAD) mice was examined. Administration of 9-cis-RA stimulated the differentiation and subsequent proliferation of the growth-arrested A spermatogonia in the testis of VAD mice. However, compared with all-trans-retinoic acid (ATRA), relatively higher doses of 9-cis-RA were necessary. This could not simply be due to a lower or delayed activity of 9-cis-RA, as simultaneous administration of ATRA and 9-cis-RA did not cause a synergistic effect. Instead, the presence of 9-cis-RA diminished the effect of ATRA by approximately one third. Studies of in vivo transport and metabolism showed that ATRA and 9-cis-RA, after administration to VAD mice, penetrated the testis equally well. However, 9-cis-RA was metabolized much faster than ATRA, and other metabolites were formed. This may account for the above-described differential effects of ATRA and 9-cis-RA on spermatogenesis. Similar to ATRA, 9-cis-RA transiently induced the messenger RNA expression of the nuclear RA receptor RAR beta, suggesting a role for this receptor in the effects of retinoids on the differentiation and proliferation of A spermatogonia. In contrast, the messenger RNA expression of the nuclear retinoid receptors RXR alpha, -beta, and -gamma was not changed significantly by administration of their ligand, 9-cis-RA. Hence, 9-cis-RA does not seem to exert its effect on spermatogenesis through altered expression of the RXRs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
139
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4269-76
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
The effect of 9-cis-retinoic acid on proliferation and differentiation of a spermatogonia and retinoid receptor gene expression in the vitamin A-deficient mouse testis.
pubmed:affiliation
Department of Cell Biology, Medical School, Utrecht University, The Netherlands. gaemers@nki.nl
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't