甲醛慢性吸入暴露致小鼠精子畸形

目的研究甲醛慢性吸入染毒致雄性小鼠生殖细胞遗传毒性。方法 SPF级雄性ICR小鼠40只,随机分为4组:低剂量组、高剂量组、阴性对照组和阳性对照组,每组10只,低、高剂量组染毒剂量分别为1、10 mg/m~3,用静式吸入的方法进行染毒,每天一次,每次2 h,连续染毒20周,阳性对照组给予环磷酰胺。小鼠染毒后继续饲养5周。观察并计算精子畸形率。结果阴性对照组、低剂量组和高剂量组的睾丸脏器系数分别为(0.81±0.13)%、(0.82±0.12)%和(0.78±0.12)%,各组之间差异无统计学意义(P0.05);阴性对照组、阳性对照组、低剂量组和高剂量组的精子畸形率分别为4.1%、6.4%、11.5%和11.3%,与阴性对照组比较,各染毒组精子畸形率明显增加,差异有统计学意义(P0.01);且染毒剂量与精子畸形率之间存在剂量-反应关系(r_s=0.888,P0.01)。结论甲醛慢性吸入染毒可引起小鼠精子畸形率升高,且染毒剂量与精子畸形率之间存在剂量-反应关系。

Sperm abnormalities in male mice induced by chronic inhalation exposure to formaldehyde

Objective To study the genetic toxicity to germ cell of male mice induced by chronic inhalation exposure to formaldehyde.Methods Forty male ICR mice were randomly divided into four groups,such as negative control group,positive control group and two exposure groups(1,10 mg/m3 formaldehyde).The mice were treated with static inhalation of formaldehyde for two hours,once a day for 20 weeks.Then the mice were fed for five weeks after exposure,and epididymides sperm smears were made and the number and type of abnormal sperm were observed and counted under a microscope,and the sperm abnormalities rate were calculated.The testis index of the mice was also measured.Results The testis index of the mice in the negative control group and the two exposure groups (1,10 mg/m3) were (0.81±0.13)％,(0.82±0.12)％ and (0.78±0.12)％,there were no statistically significant among them (P＞0.05).The sperm abnormalities rate in the negative control group,positive control group and two exposure groups(1,10 mg/m3) were 4.1％,6.4％,11.5％ and 11.3％ respectively,the sperm abnormalities rate in two exposure groups were statistically significant higher than those of negative control group (P＜0.05),there were doseresponse relationship between the exposure dose and the sperm abnormalities rate (rs=0.888,P＜0.01).Conclusion Chronic static inhalation of formaldehyde can increase the sperm abnormalities rate in mice,and there is dose-response relationship between the exposure dose of formaldehyde and the sperm abnormalities.