title: Oocyte meiotic-stage-specific differences in spindle depolymerization in response to temperature changes monitored with polarized field microscopy and immunocytochemistry.
abstract: OBJECTIVE
  To compare the polymerization status of mouse oocyte spindles exposed to various temperatures at various stages of meiosis.
  
  
  METHODS
  Experimental animal study.
  
  
  METHODS
  University animal laboratory.
  
  
  METHODS
  CF1 mice.
  
  
  METHODS
  Immature oocytes matured to metaphase I (MI), telophase I (TI), and metaphase II (MII) were incubated at 37 °C (control), room temperature (RT), or 4 °C for 0, 10, 30, and 60 minutes. Spindle analysis subsequently was performed using polarized field microscopy and immunocytochemistry. Spindles of TI and MII oocytes that underwent vitrification and warming were analyzed also by immunocytochemistry.
  
  
  METHODS
  Detection of polymerized meiotic spindles.
  
  
  RESULTS
  At RT, and after 60 minutes at 4 °C, a significant time-dependent decrease in the percentage of polymerized meiotic spindles was observed in MI and MII oocytes, but not in TI oocytes. The polymerization of TI spindles at 4 °C was similar to that of TI spindles at 4 °C that underwent vitrification and warming.
  
  
  CONCLUSIONS
  Significant differences in the microtubule dynamics of MI, TI, and MII oocytes incubated at different temperatures were observed. In particular, meiotic spindles in TI oocytes exhibited less depolymerization than did metaphase spindles.
authors.affiliation: Department of Gynecology, Medical School, University of São Paulo, São Paulo, Brazil. cgomes@huntington.com.br
authors.forename: Claudia
authors.initials: C
authors.lastname: Gomes
authors.forename: Mariana
authors.initials: M
authors.lastname: Merlini
authors.forename: Jeremy
authors.initials: J
authors.lastname: Konheim
authors.forename: Paulo
authors.initials: P
authors.lastname: Serafini
authors.forename: Eduardo L A
authors.initials: EL
authors.lastname: Motta
authors.forename: Edmund C
authors.initials: EC
authors.lastname: Baracat
authors.forename: Gary D
authors.initials: GD
authors.lastname: Smith
mesh_terms: D000818:Animals; D003080:Cold Temperature; D005260:Female; D007150:Immunohistochemistry; D008540:Meiosis; D051379:Mice; D008859:Microscopy, Polarization; D009865:Oocytes / Q000378:metabolism*; D008941:Spindle Apparatus / Q000378:metabolism*; D013997:Time Factors; D014404:Tubulin / Q000378:metabolism*; D058989:Vitrification
chemical_list: D014404:Tubulin