臺灣博碩士論文加值系統

得克利（tebuconazole）是一種三唑類(triazole)殺黴菌劑，常用於果樹如 : 蘋果、梨、梅、桃、枇杷、茶、乾豆等作物。三唑類農藥的生殖毒性及內分泌干擾作用受到國際農藥管理單位重視，2010年美國環保署「優先研究環境荷爾蒙活性之物質」清單包括三唑系農藥，其中得克利也在其中 (U.S.EPA, 2010)。在先前的研究指出，得克利可經由子宮及哺乳的途徑造成仔鼠雌化表型的改變，而得克利短期投藥7天對於已切除睪丸幼雄鼠並不具抗雄性激素作用。目前尚無文獻探討得克利亞急性投藥28天對性成熟動物之內分泌干擾作用之研究，且至今仍無得克利調控活體藥物代謝之資料。本研究主要目標在探討得克利對於雄鼠的內分泌干擾作用及肝臟和睪丸藥物代謝酶活性之影響。雄性大鼠以胃管給予劑量10、25及50 mg/kg得克利，每日一次，連續餵食28天。研究結果發現，給予劑量10、25及50 mg/kg得克利造成副睪的精子數目減少，這種殺菌劑對於睪丸的精子數目表現也出現減少的趨勢，但是並沒有統計學上的意義。在酵素免疫分析上，試驗結果發現，給予劑量10、25及50 mg/kg得克利會降低雄性大鼠血清睪固酮(testosterone)的濃度。得克利也會誘導肝臟微粒體(microsome)細胞色素P450和細胞色素b5含量上升，並增加7-ethoxyresorufin O-deethylase、pentoxyresorufin O-deethylase、7-ethoxycoumarin O-deethylase、aniline hydroxylase和erythromycin N-demethylase的活性，且具有劑量效應關係；而在睪丸微粒體中發現，得克利在劑量效應關係之下，會降低7-ethoxyresorufin、methoxyresorufin、pentoxyresorufin、aniline和erythromycin的代謝活性。反轉錄聚合酶連鎖反應的結果表示，得克利會誘導肝臟的CYP1A1、CYP2B和CYP3A1 mRNA表現，但對睪丸的CYP mRNA表現並沒有明顯影響。目前研究結果得知，得克利是一種內分泌干擾物，在雄性大鼠給予得克利的結果表示，具有降低精子數目、血清睪固酮濃度及調節藥物代謝的能力。本研究成果提供得克利新的毒理學資訊，並可能有助於此環境賀爾蒙農藥影響內分泌活性之殺菌劑的健康風險評估及管理。

Tebuconazole is a triazole fungicide, commonly used in fruit trees such as: apple, pear, plum, peach, coriander, tea, dried beans and other crops. The reproductive toxicity and endocrine disruption of triazole pesticides have been valued by international pesticide management agencies. In 2010 the US Environmental Protection Agency ’s list of “priority research on environmental hormone activity” also includes triazole pesticides (U.S.EPA, 2010). Previous studies have pointed out that tebuconazole can change the female phenotype of pups through the uterus and lactation, and tebuconazole does not have anti-androgenic effects for 7 days after the short-term administration of tebuconazole in young male rats those had already removal of testis. At present, there is no literature on the effect of 28-day administration of tebuconazole decreasing on the endocrine disruption of sexually mature animals, and there is still no data on the drug metabolism of tebuconazole in vivo study. The main objective of this study was to investigate the effects of decreasing on the endocrine disruption of male rats and the activities of drug metabolism and enzymes in the liver and testes. Male rats were administered 10, 25, and 50 mg / kg of tebuconazole by gastric tube lavage once a day for 28 consecutive days. The results of the study found that the administration of 10, 25 and 50 mg / kg tebuconazole caused a decrease in the number of sperm in the epididymis. This fungicide also showed a decrease in the number of sperm in the testes, but it had no statistical significance. Enzyme immunoassay test results found that 10, 25, and 50 mg / kg tebuconazole decreased serum testosterone concentration. Tebuconazole induced liver microsomal cytochrome P450 and cytochrome b5 levels and increased the activity of 7-ethoxyresorufin O-deethylase, pentoxyresorufin O-deethylase, 7-ethoxycoumarin O-deethylase, aniline hydroxylase, and erythromycin N-demethylase, showing a dose-response relationship. In testis microsomes it was found that under the dose-response relationship, tebuconazole would reduce the metabolic activities of 7-ethoxyresorufin, methoxyresorufin, pentoxyresorufin, aniline and erythromycin. The results of reverse transcription polymerase chain reaction showed that tebuconazole induced the expression of CYP1A1, CYP2B and CYP3A1 mRNA in the liver, but had no effect on the CYP mRNA expression of testes. Current research results show that tebuconazole is an endocrine disruptor. The results of tebuconazole administration in male rats indicate that it has the ability to reduce sperm count, serum testosterone concentration and regulate drug metabolism. The results of this research provide the toxicological information of tebuconazole and may be helpful for the health risk assessment and management of environmental hormones fungicides that affect endocrineactivity.

目 錄 ....................................................................................I
口試委員會審定書....................................................................II
誌謝..............................................................................III
中文摘要............................................................................1
英文摘要............................................................................3
List of Tables......................................................................5
List of Figures.....................................................................6
Title : 農藥得克利對雄鼠細胞色素P450、氧化壓力及內分泌干擾作用之研究 (Effects of Tebuconazole on Cytochromes P450, Oxidative Stress and Endocrine Disruption in Male Rats)...............................................................................8
引言................................................................................9
材料與方法材料與方法................................................................15
結果...............................................................................21
討論...............................................................................29
結論...............................................................................34
參考文獻...........................................................................35
表格...............................................................................46
圖及圖示Figures and figure legends.................................................57
補充表格Supplementary tables.......................................................65
補充圖示Supplementary figures (liver)..............................................68
補充圖示Supplementary figures (testis).............................................79
附錄List of Publications.....................................................................101

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