Linked Life Data

2202516

Source:http://linkedlifedata.com/resource/pubmed/id/2202516

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1990-10-1
pubmed:abstractText
We describe a double labelling method for estimating the duration of DNA synthesis (Ts) and the flux of cells into and from the S phase of the cell cycle, based on labelling with tritiated thymidine [( 3H]TdR) followed by bromodeoxyuridine (BrdU) and combining immunohistological detection of BrdU with conventional autoradiography. In practice, the change in size of a window of double labelled cells occurs as the time interval between the two labels increases. In mouse tongue epithelium there is a marked circadian variation in the number of cells in DNA synthesis. From 0900 to 1500 h this labelling index (LI) falls, but from 2100 to 0300 h it increases. Our results show that the circadian decrease in LI is associated with a short Ts (5.8 +/- 0.3 h), a high S phase efflux and an initially low influx of cells from G1 into S. Conversely, the rising circadian LI is associated with a longer Ts (9.4 +/- 0.1 h), an initially low efflux and a moderate to high influx. Two time-points exist on the circadian LI curve when influx and efflux rates change abruptly. At 0100 h the efflux rate rises from low (5 cells %/h) to high (15-16 cells %/h) and simultaneously the influx rate changes from high to low. Similarly at 1300-1400 h, efflux rate falls from high (19-20 cells %/h) to low (4-8 cells %/h) values and influx rates change from low to high. This double labelling method has revealed that the duration of DNA synthesis varies across the circadian cycle, as do influx and efflux values which generally fall within a discrete range of high or low values. The timing of the changes in flux suggests the presence of two 'control' points on the circadian LI cycle that were previously unrecognized.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0008-8730
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
313-23
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Double labelling of cells with tritiated thymidine and bromodeoxyuridine reveals a circadian rhythm-dependent variation in duration of DNA synthesis and S phase flux rates in rodent oral epithelium.
pubmed:affiliation
Department of Dental Surgery, Leeds University Dental School, U.K.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't