在防治含氯有機溶劑污染水源與土壤的研究課題上，應用細胞培養技術，以明瞭並減低人類公共衛生所承受的危險，將是個有力工具。就三氯乙烯與四氯乙烯而言，已經是一個普遍公認的工業化所造成的環境污染問題，因為此化學物質在工業上所使用的範圍非常地廣泛。本篇研究的目標在於利用中國倉鼠細胞，印證動物活體於三氯乙烯及四氯乙烯在不同濃度，對細胞的生長抑制和生化代謝毒性的影響。 就中國倉鼠卵巢細胞對於三氯乙烯與四氯乙烯的毒性確認，是基於將細胞接種於活體外的揮發暴露系統中。在特製60 mm 培養皿中間區域部分，另外貼黏著一個25-mm 大小的玻璃培養皿，以提供加入揮發性藥劑所需要的區域。個別處理三氯乙烯或四氯乙烯的劑量分別是三氯乙烯20-80 ul ，四氯乙烯5-20 ul ；其中利用藥劑揮發後I變成氣體，再溶到培養液中。進而研究其影響細胞的生理與生化之反應。得到中國倉鼠卵巢細胞對三氯及四氯乙烯的毒性影響有：細胞的生長抑制、細胞內的酵素活性、細胞內GSH 的濃度等。其中明顯隨著添藥量增加而明顯增加的是：生長抑制現象與微小核增加頻率等。此外也發現在低劑量處理時 (三氯乙烯5-20 ul ，四氯乙烯1-5 ul) GSH 含量反而會隨之增加。增加量約為1.5 倍正常量。但當添藥量超過之後GSH 則是快速的下降。除此之外在GST 的活性方面，活性強度隨著處理藥劑濃度的增加，而有明顯的增加，上升的倍數約為三倍值。比較GSH 含量不同之後發現，隨著藥劑濃度增加，而並沒有顯著地改變細胞的生長抑制現象。在三氯與四氯乙烯對中國倉鼠卵巢細胞毒性上，GSH-conjugate 可能是一個中間反應；然而GSH-dependent 的活化作用在中國倉鼠卵巢細胞中，對三氯與四氯乙烯的biotransformation 上扮演了一個次要的解毒角色。 The development and validation of cell culture techniques for estimating chlorine contained organic solvents in contaminated soil and water can facilitate the overall understanding of anamal health risk. Currently, trichloroethylene (TCE) and tetrachloroethylene (PCE) are the major environmental contaminant and an occupational concern issues because of their widespread industrial use. The objective of this study was to use the cell culture techniques (Chinese hamster ovary cells, CHO-K1) to determine the toxicity of the toxicity of trichloroethylene (TCE) and tetrachloroethylene (PCE) on the CHO-K1. The CHO-K1 cells were grown in a 60-mm petri dish with a 25-mm glass dish glued in the central area. The TCE (20-80 ul) or PCE (5-20 ul) was added to the central glass well, and let it to evaporate and dissolve in the surrounding medium in which cells were growing. Treatment of CHO-K1 cells with either TCE or PCE resulted in a dose and exposure inhibition of cell growth. A statistically significant increase in the frequency of MN (micronuclei test) was also observed in either TCE or PCE-treated CHO-K1 cells. Low dose of TCE (5-20 ul) or (1-5 ul) treatments showed significantly enhancement the intracellular glutathione (GSH) levels. However, the level of GSH rapidly decreased in the presence of higher dose of TCE (40-80 ul) or PCE (10-20 ul). Furthermore, the GST activity was enhanced by TCE- or PCE- treatment. Depletion of cellular GSH showed no effect on the sensitivity of CHO-K1 cells to TCE- or PCE- treatments. The GSH-conjugate has been proposed as a reactive intermediate, which is account for the toxicity of TCE and PCE, however the GSH-dependent activation play a minor role in the biotransformation of TCE and PCE in CHO-K1cells.
