title: Evaluation of maturation competence of metaphase II oocytes in mice based on the distance between pericentriolar materials of meiotic spindle: distance of PCM during oocyte maturation.
abstract: OBJECTIVE
  To ascertain whether metaphase II (MII) spindle shape influences oocyte competence, we examined the meiotic spindle organization in in vivo ovulated (IVO) oocytes and in spontaneously matured or follicle stimulating hormone (FSH)-induced oocytes.
  
  
  METHODS
  FSH-induced oocytes matured in Waymouth's MB752/1 or human tubal fluid (HTF) media and oocytes matured spontaneously in the basal medium were obtained, and spindles were detected by immunofluorescence. To evaluate the fertilization-associated differences in spindle morphology, we performed in vitro fertilization and analysed integrin mRNA expression.
  
  
  RESULTS
  The distance between the pericentriolar materials (PCMs) in oocytes matured under all conditions was initially more, but it reduced gradually and increased again thereafter. Therefore, oocytes exhibiting a reduction in the distance between PCMs had the highest development rate to blastocyst in each condition.
  
  
  CONCLUSIONS
  These results indicate that the 'maturation competence' of MII oocytes can be evaluated on the basis of the distance between PCMs.
authors.affiliation: Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, Sendai, 981-8555, Japan. chizuka@bios.tohoku.ac.jp
authors.forename: Chizuka
authors.initials: C
authors.lastname: Sakai
authors.forename: Yumi
authors.initials: Y
authors.lastname: Hoshino
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sato
authors.forename: Eimei
authors.initials: E
authors.lastname: Sato
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000502:physiology; D018385:Centrosome; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000235:genetics / Q000494:pharmacology*; D015870:Gene Expression / Q000235:genetics; D016023:Integrins / Q000235:genetics; D008540:Meiosis / Q000187:drug effects / Q000235:genetics; D008677:Metaphase; D051379:Mice; D015877:Miosis; D009865:Oocytes / Q000166:cytology* / Q000254:growth & development; D009866:Oogenesis / Q000187:drug effects / Q000235:genetics; D008941:Spindle Apparatus / Q000187:drug effects / Q000235:genetics / Q000648:ultrastructure*
chemical_list: D016023:Integrins; D005640:Follicle Stimulating Hormone