鄰苯二甲酸二（乙基己基）酯 (Di (2-ethylhexyl) phthalate，DEHP) 近幾年來大量被添加在塑膠材質的製品中當作軟化劑、塑造劑。由於它是以非共價鍵結的方式與塑膠材質的製品結合，因此，DEHP可以很容易地從日常生活用品中滲漏到環境中。先前的研究指出，DEHP可以經由胎盤或乳汁傳遞給子代，進而影響雄性動物的生殖表現，例如：縮短肛門到生殖口的距離、增加乳突滯留的時間、精子形成之異常、或是減少精子數。因此，本研究將以每天灌食方式暴露懷孕第11天到第20天的母鼠100, 或500 mg DEHP/kg bw/day，並且每個禮拜都紀錄雄性子代的體重及肛門到生殖口的距離。在子代84-90天大時，除了測定精子數、活動力，並應用以電腦來輔助的精子運動分析儀器 (computer-aided sperm analysis) 偵測精子運動路徑，以及24小時體外穿透實驗探討精子的穿透能力是否受到影響。結果，我們發現當母鼠在懷孕時期受到500 mg DEHP/kg bw/day暴露後，其雄性子代的肛門到生殖口的距離有縮短的傾向。雖然，精子的活動力及運動路徑並沒有明顯受到影響，但，有較少具備活動力的精子數。此外，在24小時體外受孕研究中，我們發現，當雄鼠在出生前受到500 mg DEHP/kg bw/day暴露，其精子有較差的能力去穿透卵子。因此，我們推測，若懷孕後期的雄性胎兒受到DEHP暴露，則可能會影響其成年時的雄性生殖表現，不只是會有較少具備活動力的精子，還可能會有較差的穿透透明帶的能力。

　　Di (2-ethylhexyl) phthalate (DEHP) is a plasticizer used rather commonly in a variety of polyvinyl chloride-based consumable products. Previous studies have reported that DEHP exposure during the perinatal to puberty could adversely affect the reproductive development of male rodents. They included reduced anogenital distance on postnatal day 1, increased incidence of nipple retention, abnormal spermatogenesis, and decreased sperm number in an anti-androgenic manner. The present study was designed to explore whether prenatally DEHP exposure affected profoundly anogenital distance development or sperm function. We gavaged pregnant rat on gestation day 11 to 20 with 1.6ml corn oil, 100, or 500 mg DEHP/kg bw/day, and subsequently recorded male offspring body weight and AGD weekly until sacrificed. Sperm count, motility, movement track and in vitro penetration assay were also studied on postnatal day 84-90. We found that treated male rats at 500 mg DEHP/kg bw/day showed a reduced anogenital distance trend, and decreased motile sperm number and percentage of penetrated oocyte in vitro. However, sperm motility and motion were not different with control. Therefore, we conclude that not only sperm count and motile sperm number in adulthood were decreased, but the capability of sperm penetrating zona-intact oocyte was impaired by prenatally DEHP exposure.

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