Linked Life Data

17643482

Source:http://linkedlifedata.com/resource/pubmed/id/17643482

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-8-7
pubmed:abstractText
Exposure of oocytes to elevated temperature (i.e. heat shock) during maturation can reduce fertilization rate and development of the resultant embryos. Given the possible role of free radicals in actions of heat shock on cellular function, we tested the hypothesis that a high oxygen environment exacerbates the magnitude of deleterious effects of heat shock on in vitro maturation of bovine oocytes. A preliminary experiment was performed to establish conditions for oocyte maturation that would be independent of oxygen concentration. Oocytes were matured in a modified tissue culture medium-199 (mTCM-199) or modified synthetic oviduct fluid (mSOF) containing 5.6 or 20 mM glucose and under either high (atmospheric oxygen, approximately 21%, v/v) or low oxygen (5%, a value approximating oxygen content of the follicle). For oocytes matured in mTCM-199, development was greater in high oxygen than in low oxygen, whereas development was unaffected by oxygen using mSOF (mediumxoxygen, P<0.05). Accordingly, mSOF was used as the maturation medium in a second study to test the effect of oxygen concentration on the magnitude of actions of heat shock during maturation. Maturation was at 38.5 degrees C for 22 h (control) or 41 degrees C for 12h and 38.5 degrees C for 10h (heat shock). Heat shock slightly decreased cleavage rate, regardless of the maturation conditions, and decreased blastocyst development under all maturation conditions except for the group matured under high oxygen and high glucose (temperature x glucose for oocytes under low oxygen, P<0.05). The percentage of oocytes becoming blastocysts for control and heat shocked oocytes was 25.9% versus 22.5% (low oxygen -- 5.6 mM glucose), 41.6% versus 34.9% (low -- 20 mM), 41.7% versus 35.0% (high -- 5.6 mM), and 37.6% versus 37.5% (high -- 20 mM). In conclusion, under an oxygen tension that approached physiological conditions, heat shock during in vitro maturation reduced oocyte competence for fertilization and subsequent development.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0093-691X
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
763-70
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Interactions between oxygen tension and glucose concentration that modulate actions of heat shock on bovine oocytes during in vitro maturation.
pubmed:affiliation
Department of Animal Sciences, University of Florida, Gainesville, FL 32611-0910, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't