摘要
用光镜和电镜观察环氧乙烷（ＥｔＯ）对精子形成的影响。Ｗｉｓｔａｒ雄性大鼠，静式吸入染毒，浓度为０、９０、３６０和８００ｍｇ／ｍ３，２ｈ／日，６日／周，连续染毒１３周或９周。结果表明，ＥｔＯ引起睾丸重量减轻，附睾尾精子数及活精率降低。低浓度（９０ｍｇ／ｍ３）组，电镜下可见少数异常形态结构的精子细胞和畸形精子尾丝。３６０ｍｇ／ｍ３组，染毒１３周，光镜下可见睾丸边缘部分曲细精管出现空泡，生精细胞减少，偶见多核巨细胞。电镜下观察，部分精细胞和支持细胞中线粒体受损及许多各种不同变态发育阶段的畸形精细胞，附睾尾精子畸形率明显升高。高浓度（８００ｍｇ／ｍ３）ＥｔＯ染毒９周，停止染毒４周后，生精细胞严重变性、坏死，曲细精管明显萎缩，生精细胞大部分消失。电镜下观察，所有精细胞崩解，附睾尾少精、死精或无精。结果提示，亚慢性吸入８００ｍｇ／ｍ３ＥｔＯ时，引起睾丸萎缩，出现死精或无精，损伤是不可恢复的。长期吸入低浓度ＥｔＯ对大鼠精子形成有影响，其中最敏感的是精细胞变态发育成精子的发育阶段。
Wistar male rats were exposed to ethylene oxide (EtO) at dose of 0,90,360 or 800mg/m 3 for 2h a day,6 days a week,for 9 or 13 weeks.Effects of subchronic inhaled EtO on spermatogenesis were investigated in rats.The results showed that EtO induced decreases in weights of testis and accessory sex organs,sperm counts and sperm motility and increases in numbers of abnormal sperm in the tail of epididymis.In light and electron microscopic examination,a small number of abnormal spermatid were found at dose of 90mg/m 3.At a dose of 360mg/m 3,focal slight degeneration of seminiferous tubules,swelling,degeneration or breaking of mitochondria in some spermatid and Sertoli′s cells and a great many abnormal spermatid were noted.At a dose of 800mg/m 3,after exposed to EtO for 9 weeks and stopped for 4 weeks,severe degeneration,necrosis of germ cells and all the spermatid disintegration were observed and there were only a small and dead sperm in the tail of epididymis.The results indicate that subchronic inhalation of EtO induces testicular atrophy and spermatacrasia in rats and the damage is inrecoverable at 800mg/m 3.Subchronic inhalation of EtO affects spermatogenesis in rats at low dose.The stage of spermatid developing into spermatozoa is the most sensitive.
基金
国家自然科学基金
