Linked Life Data

11933168

Source:http://linkedlifedata.com/resource/pubmed/id/11933168

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-4-4
pubmed:abstractText
In this study, the effects of meiotic status on the energy substrate dynamics of mouse oocyte-cumulus cell complexes (OCCs) and denuded oocytes (DOs) have been examined. In the first series of experiments, OCCs from PMSG-primed, immature mice were cultured in minimum essential medium in 8-microl microdrops under a variety of conditions, and the medium and oocytes were sampled for pyruvate and glucose concentration and for meiotic status. Oocytes in control medium underwent germinal vesicle breakdown within 3 hr and the OCCs displayed a time-dependent increase in pyruvate consumption, but the glucose concentration changed very little. Treatment with IBMX or dbcAMP, which maintained complete meiotic arrest, suppressed pyruvate consumption, but slightly more glucose was consumed than in controls. Hypoxanthine (HX) allowed up to 10% of the oocytes to resume maturation, and pyruvate and glucose consumption resembled that of control OCCs. FSH added to HX-containing medium stimulated significant glucose consumption and pyruvate production. In general, a reciprocal relationship was observed between glucose and pyruvate consumption. When the energy substrate dynamics were compared with meiotic status of the oocytes, pyruvate consumption was associated with the maturation process. Although HX maintained oocytes in the germinal vesicle stage, the meiotic arrest was "leaky," allowing increased pyruvate consumption. Additional experiments showed that DOs at either the prophase I or metaphase II stages consumed less pyruvate than oocytes actively engaged in meiotic maturation. DOs oxidized significantly more pyruvate than OCCs, and glycolytic metabolism of glucose lowered the oxidation rate in OCCs. Furthermore, while 5-6.2 times more pyruvate was consumed by OCCs than by DOs in the absence of glucose, oxidation did not mediate the meiosis-inducing effect of pyruvate, since less of this substrate was oxidized by OCCs than by DOs. We conclude that meiotically active oocytes have a greater requirement for pyruvate than prophase I- or metaphase II-arrested oocytes and that meiotic status can influence the metabolism not only of oocytes, but also of the OCCs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1040-452X
pubmed:author
pubmed:copyrightInfo
Copyright 2002 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
113-23
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Pyruvate utilization by mouse oocytes is influenced by meiotic status and the cumulus oophorus.
pubmed:affiliation
Biology Department, Marquette University, 530 N 15 Street, Milwaukee, WI 53233, USA. stephen.downs@marquette.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.