title: [Instillation of diesel exhaust particles on the posterior wall of pharynx on reproductive function in female mice].
abstract: OBJECTIVE
  The present work aims to investigate the effects of subacute exposure to diesel exhaust particles (DEP) on reproductive function in female mice.
  
  
  METHODS
  A total of 168 ICR (Institute of Cancer Research) mice were randomly divided into four groups by numeration table method, including the low (B), middle (C), high (D) dose DEP exposure groups and the control group (A). Each group consisted of 42 mice. Mice were inoculated with 30 µl DEP suspension at 0.8 (B), 3.0 (C), 12.0 (D) µg/µl, respectively, or the same volume of phosphate-buffered saline (A) on pharynx posterior wall per triduum for 4 times. The body weight and ovary weight were tested and ovary weight/body weight ratios were calculated. Rates of survival, germinal vesicle breakdown, extrusion of the first polar body, in-vitro fertilization and quantity of mitochondrial DNA for the oocytes were investigated. Ultrastructural changes of the oocytes were observed.
  
  
  RESULTS
  The ovary weight/body weight ratios were (15.4 ± 7.3) × 10(-5), (14.1 ± 6.8) × 10(-5), (8.2 ± 0.7) × 10(-5) and (7.2 ± 2.5) × 10(-5) in groups A, B, C and D (F = 3.841, P < 0.05). In groups A, B, C and D at 48 h post-insemination, rates of oocyte survival were 64.3%, 56.8%, 39.5% and 32.9% (χ(2) = 21.575, P < 0.05), rates of extrusion of the first polar body were 75.5%, 65.3%, 37.0% and 27.1% (χ(2) = 52.772, P < 0.05), rates of 2-cell embryos were 27.9%, 39.1%, 17.6% and 12.5% (χ(2) = 20.148, P < 0.05), and rates of embryos over 2 cells were 45.3%, 32.2%, 12.5% and 13.9% (χ(2) = 32.135, P < 0.05), respectively, and were significantly lower in groups C and D compared with group A (P < 0.05). Logarithmic values of mitochondrial DNA copy numbers were 6.54 ± 0.13, 6.48 ± 0.09, 5.57 ± 0.15 and 5.41 ± 0.07 in groups A, B, C and D, respectively, and were significantly lower in groups C and D compared with group A or B (F = 89.241, P < 0.05). A number of mitochondria of the oocytes exhibited tremendous tumescence and vacuolization in groups C and D, which was contrast to a roughly normal appearance in groups A and B.
  
  
  CONCLUSIONS
  DEP is noxious to murine female reproduction. Subacute exposure to DEP injures the ovary and oocyte resulting in compromised ovarian function and fertilizability of the oocyte.
authors.affiliation: Department of Obstetrics and Gynecology, Fuzhou General Hospital of Nanjing Command, Fuzhou 350025, China. hxr0812@163.com
authors.forename: Xin-ru
authors.initials: XR
authors.lastname: Hong
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Yan-feng
authors.initials: YF
authors.lastname: Song
authors.forename: Xiao-qiu
authors.initials: XQ
authors.lastname: Chen
authors.forename: Ling
authors.initials: L
authors.lastname: Zheng
authors.forename: Hong-yu
authors.initials: HY
authors.lastname: Yu
mesh_terms: D000818:Animals; D005260:Female; D051379:Mice; D008813:Mice, Inbred ICR; D009865:Oocytes / Q000187:drug effects*; D010053:Ovary / Q000166:cytology / Q000187:drug effects*; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D001335:Vehicle Emissions