工频电磁场接触对大鼠生殖功能的影响

Animal Experimental Studies of Power Frequency Electromagnetic Field Exposure on Reproductive Function of Rats

目的评价工频电磁场接触对大鼠生殖功能的影响，用以研究人类的电磁场接触对生殖功能的损伤风险。方法自行设计制备磁场发生仪，把大鼠暴露于一定强度的磁场中生活一段时间。观察雌性大鼠的甾体激素水平、动情周期和生殖状况和数量；并观察雄性大鼠的睾丸和附睾重量、精子密度、活动精子比例和精子质膜完整性。结果本实验发现工频电磁场强度达1mT，每日暴露时间8h，自4周龄开始持续1个月，不会对雌性大鼠成年后甾体激素分泌情况和生育后代的情况产生显著影响，仅仅导致发情频率提高；而2mT，每日暴露12h，自8周龄开始持续2个月，可导致雄性大鼠的活动精子比例下降。结论在大鼠卵母细胞和精子发生过程中，环境工频磁场会导致雌性大鼠的发情频率增加，雄性大鼠的活动精子比例下降。

Objective An instrument of power frequency electromagnetic fields, applicable for an animal model with rats as experimental subjects, will be designed to evaluate risk of the damage on reproductive functions under low frequency electromagnetic field exposure. Method The rats were exposed to the magnetic field at certain intensity for some time. Some parameters of reproductiue function were measured including plasma levels of steroid hormones, estrous cycle, and the numbers and development status of the offspring in females, and weight of the testis and epididymis, sperm density, the proportion of motile sperms, and sperm plasma membrane integrity. Results The study found that one month exposure of lmT electromagnetic field, 8hours daily, initiated at the age of 4 weeks didn＇t induced significant change in the secretion of hormones and fertility in females, only increased estrus frequency, in the power frequency electromagnetic field at linT, and with daily exposure time of 8 hours, for a month since the beginning at age of 4 weeks, the grown adult female rats have not shown a significant change in the secretion of hormones and fertility to bear future generations, and only estrus frequency increased, two month exposure of 2mT electromagnetic field, 12hours daily, initiated at the age of 8 weeks induced the decline of sperm motility of males.