咽后壁滴注柴油机尾气颗粒物对雌性小鼠生殖功能的影响

目的 观察柴油机尾气颗粒物(DEP)亚急性暴露对雌性小鼠生殖功能的影响.方法 将168只ICR( Institute of Cancer Research)雌性小鼠按数字表法随机分为低(B)、中(C)、高(D)剂量DEP暴露组和对照组(A),每组42只,分别向B、C、D组小鼠咽后壁滴注0.8、3.0、12.0 μg/μl DEP混悬液及PBS各30μl,每3天重复滴注1次,共4次.测量小鼠体重及卵巢重量,计算卵巢重量/体重,检测卵母细胞的存活率、胚泡破裂百分率、第一极体释放百分率、受精率、线粒体DNA含量和超微结构的变化.结果 A、B、C、D组卵巢重量/体重分别为(15.4±7.3) ×10-5、(14.1±6.8) ×10-5、(8.2±0.7) ×10-5和(7.2±2.5)×10-5 (F=3.841,P＜0.05).A、B、C、D组加入精子后第48小时,卵母细胞存活率分别为64.3％、56.8％、39.5％、32.9％(x2=21.575,P＜0.05),第一极体释放率分别为75.5％、65.3％、37.0％、27.1％ (x2 =52.772,P＜0.05),2细胞胚胎率分别为27.9％、39.1％、17.6％、12.5％(x2=20.148,P＜0.05),2细胞以上胚胎率分别为45.3％、32.2％、12.5％、13.9％ (x2 =32.135,P＜0.05).A、B、C、D组卵母细胞线粒体DNA的拷贝数对数值分别为6.54±0.13、6.48±0.09、5.57±0.15和5.41±0.07(F =89.241,P＜0.05).C、D组卵母细胞许多线粒体肿胀、空泡化,A、B组卵母细胞结构无明显改变.结论 DEP具有雌性生殖毒性.亚急性DEP暴露可对卵巢及卵母细胞造成不同程度损伤,降低卵巢功能和卵母细胞受精能力.

Instillation of diesel exhaust particles on the posterior wall of pharynx on reproductive function in female mice

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％ ( x2 =21.575,P ＜ 0.05 ),rates of extrusion of the first polar body were 75.5％,65.3％,37.0％ and 27.1％ ( x2 =52.772,P ＜ 0.05 ),rates of 2-cell embryos were 27.9％,39.1％,17.6％ and 12.5％ ( x2 =20.148,P ＜ 0.05 ),and rates of embryos over 2 cells were 45.3％,32.2％,12.5％ and 13.9％ (x2 =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.