Linked Life Data

4070548

Source:http://linkedlifedata.com/resource/pubmed/id/4070548

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-1-6
pubmed:abstractText
A slow temperature transient from 37 to 42 degrees C over 3 hr instead of the usual rapid 4- to 7-min transient increases thermal resistance twofold in MTC tumor cells and yet reduces the rates of synthesis of the 70- and 22-kDa heat-stress proteins (hsp) immediately prior to and during expression of thermal resistance--2 to 8 hr after reaching 42 degrees C [S. P. Tomasovic, P. A. Steck, and D. Heitzman, Radiat. Res. 95, 399-413 (1983)]. However, examination of hsp synthesis at earlier times reaching 42 degrees C (0.5 to 2 hr) has revealed differential expression of the individual hsp that is dependent on the rate of heating. Within 30 min of reaching 42 degrees C, cells exposed to slow transients had higher rates of synthesis of the 112- and 90- but not the 70-kDa hsp. However, cells exposed to rapid transients had a higher rate of synthesis of the 70-kDa hsp by 1 hr after reaching 42 degrees C. The rate of synthesis of the 22-kDa hsp was similar in cells heated by either method. Rates of synthesis of the 112-, 90-, and 22-kDa hsp in cells exposed to rapid transients did not equal or surpass the rates for cells exposed to slow transients until between 2 and 3 hr of heating, just before expression of thermal resistance. Rate of heating also had differential effects on total protein synthesized and transport. The total protein synthesized was observed to be 40% higher in slow-transient-treated cells over the first 2 hr. Transport of an amino acid analog, aminoisobutyric acid, was significantly inhibited in rapid-transient cells immediately after reaching 42 degrees C and had not recovered 1 or 5 hr later. Similar to total protein synthesis transport in slow-transient-treated cells was unaffected. There was no significant difference between slow- and rapid-transient-treated cells in hsp degradation, cell-cycle distribution, or amino acid pool sizes in the first 4 to 6 hr after reaching 42 degrees C. These results suggest that although the ultimate thermal dose was about 10-fold higher under slow-transient conditions, the cells receiving this treatment made regulatory or metabolic adjustments, including altered hsp synthesis patterns, that reduced initial heat damage. Either the protection of total protein synthesis or that combined with higher initial rates of synthesis of some hsp could explain the previously reported increased initial D0, increased thermotolerance, and reductions in latter hsp synthesis rates seen following slow temperature transients.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0033-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
102
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
336-46
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Heat transient related changes in stress-protein synthesis.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't