轉(zhuǎn)機(jī)因生物的研究


頁數(shù)：43 字?jǐn)?shù)：26739

摘要 1
ABSTRACT 2
1. 前言 3
1.1 轉(zhuǎn)基因生物安全性評(píng)價(jià)的必要性及評(píng)價(jià)體系的建立現(xiàn)狀 3
1.2 評(píng)價(jià)轉(zhuǎn)Bt基因抗蟲棉對(duì)魚類安全性的意義 4
1.3 對(duì)魚類安全性的評(píng)價(jià)方法 7
1.4 有關(guān)斑馬魚的研究 10
2 材料和方法 14
2.1 材料 14
2.1.1 實(shí)驗(yàn)動(dòng)物 14
2.1.2 實(shí)驗(yàn)用棉籽 14
2.1.3 試劑 14
2.1.4儀器 15
2.2 方法 17
2.2.1 實(shí)驗(yàn)處理 17
2.2.2急性毒性實(shí)驗(yàn) 18
2.2.3 慢性毒性實(shí)驗(yàn) 18
3 結(jié)果 20
3.1 急性毒性實(shí)驗(yàn) 20
3.2 慢性毒性實(shí)驗(yàn) 20
3.2.1器官和組織的形態(tài)、結(jié)構(gòu)
20
3.3 微核試驗(yàn) 24
3.3.1陽性對(duì)照物試驗(yàn) 24
3.3.2 正式實(shí)驗(yàn) 24
3.3.3 紅細(xì)胞的測(cè)量 27
4. 討論 28
4.1急性毒性試驗(yàn) 28
4.2慢性水平的毒性試驗(yàn) 29
4.3微核試驗(yàn) 31
4.4結(jié)論： 33
參考文獻(xiàn) 34
附錄Ⅰ 39
附錄Ⅱ 40
附錄Ⅲ 41
圖版說明 42


摘要
以斑馬魚(Brachydanio rerio)為實(shí)驗(yàn)材料，從一般毒性（急性，慢性），遺傳毒性兩個(gè)層次評(píng)價(jià)轉(zhuǎn)Bt基因抗蟲棉棉籽粉對(duì)魚類的生物安全性。急性毒性試驗(yàn)結(jié)果顯示轉(zhuǎn)Bt基因抗蟲棉對(duì)斑馬魚無急性致死毒性，也沒有急性非致死性毒性。慢性毒性試驗(yàn)的病理學(xué)檢查表明，肝臟、脾臟和腸均未發(fā)現(xiàn)解剖觀察水平和光鏡水平的病變。采用斑馬魚外周血紅細(xì)胞微核試驗(yàn)的遺傳毒性方法，證明誘變劑氟化鈉可以明顯誘導(dǎo)斑馬魚外周血紅細(xì)胞微核率升高，并確定了合適的陽性反應(yīng)條件。運(yùn)用改進(jìn)的小型魚采血方法和建立的斑馬魚微核試驗(yàn)檢測(cè)方法，檢測(cè)了轉(zhuǎn)Bt基因抗蟲棉的細(xì)胞遺傳毒性，結(jié)果表明轉(zhuǎn)Bt基因抗蟲棉沒有誘發(fā)斑馬魚紅細(xì)胞微核的遺傳毒性。實(shí)驗(yàn)結(jié)果表明在魚類飼料中使用規(guī)范比例的轉(zhuǎn)Bt基因棉籽粉是安全的。

關(guān)鍵詞：轉(zhuǎn)Bt基因抗蟲棉,斑馬魚,安全性評(píng)價(jià)

Abstract

The biosafety of transgenic Bt cottonseed to fish is assessed by means of regular toxicity test (acute test and chronic test) and genetoxicity test. Zebrafish (Brachydanio rerio) is chosen as model experimental animal. No acute lethal toxicity and other acute toxicity of transgenic Bt cottonseed to zebrafish is observed. After chronic toxicity test, liver, spleen and intestine of all experimental groups are examined with help of pathological methods. No pathological change on morphology level and on microscopic level is observed. Micronucleus test (MNT) is chosen on behalf of genetoxicity test. NaF is found out to be a kind of mutagens to zebrafishes and appropriate conditions for NaF to induce Micronucleus (MN) in peripheral erythrocytes is also set up. The size of peripheral erythrocytes, their nuclei, and MN is measured. The size of them shows that peripheral erythrocytes of zebrafishes are a kind of good materials for MNT. The result of MNT shows that transgenic Bt cottonseed does not induce raise of MN ratio significantly.
On base of the experimental results, a primary conclusion is made that the regular proportion of transgenic Bt cottonseed in fish meal is safe to fishes.

Key words: Transgenic Bt cottonseed, Zebrafish, Biosafety assessment