Linked Life Data

12164250

Source:http://linkedlifedata.com/resource/pubmed/id/12164250

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-8-7
pubmed:abstractText
Siberian hamsters transferred from a long (16 h light/day [16 L]) to an intermediate (13.5 L) day length (DL) undergo testicular regression within 2 months followed approximately 2 months later by "spontaneous" testicular recrudescence. Recovery of gonadal function after prolonged exposure to intermediate DLs is thought to reflect development of neuroendocrine refractoriness to intermediate-duration melatonin signals. The authors tested the alternative hypothesis that testicular recrudescence in 13.5 L occurs when the "memory" for the 16-L photoperiod fades and hamsters can no longer compare the 13.5-L to the prior 16-L day length. Adult hamsters transferred from 16 L to 13.5 L that underwent testicular involution were either maintained continuously in 13.5 L for 41 weeks or given a supplementary 2-week treatment of 16 L before being returned to 13.5 L. The supplementary treatment was administered either after hamsters had been in 13.5 L for 10 weeks and had involuted testes, or after 24 weeks, when the gonads had undergone recrudescence. The authors found that 16 L treatment administered at week 10 delayed final gonadal recrudescence by approximately 12 weeks; similar 16-L treatment at week 24 induced a second gonadal regression when animals were returned to 13.5 L. The most parsimonious hypothesis to account for these findings is that gonadal recrudescence in intermediate DLs reflects fading of the "memory" for prior long DLs rather than induction of refractoriness to melatonin signals generated in intermediate DLs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0748-7304
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
345-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Testicular recrudescence in intermediate day lengths reflects loss of photoperiodic memory in Siberian hamsters.
pubmed:affiliation
Department of Integrative Biology, University of California, Berkeley 94720, USA. ask@socrates.berkeley.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.