丙烯酰胺对雄性大鼠生殖毒性的研究

发布时间：2018-01-07 02:08

本文关键词：丙烯酰胺对雄性大鼠生殖毒性的研究　出处：《南京农业大学》2007年硕士论文　论文类型：学位论文

【摘要】： 丙烯酰胺(acrylamide，AA)为白色晶体物质，是一种重要的化工原料，广泛用于饮水净化、污水处理、造纸、采矿业及科研实验等。丙烯酰胺可经皮肤迅速吸收，是一种重要的职业接触化合物。此外，丙烯酰胺主要在高碳水化合物、低蛋白质的植物性食物加热(120℃以上)烹调过程中形成，成为非职业人群暴露的一个重要途径，因而引起广泛的关注。人体还可能通过吸烟的途径接触丙烯酰胺。丙烯酰胺具有多种毒性，可影响雄性动物生殖和发育，但其作用机制目前尚不清楚。以往研究中多采用高剂量急性染毒，而对丙烯酰胺经口长期染毒所产生的生殖毒性作用的报道较少。本研究采用亚慢性毒性试验，结合整体动物研究和体外实验，系统研究了丙烯酰胺对雄性大鼠生殖机能、脂质过氧化水平和睾丸生殖内分泌功能的影响，旨在探究丙烯酰胺对雄性生殖及睾丸内分泌功能活动产生的影响，为进一步研究丙烯酰胺对雄性生殖毒性作用及其机制提供科学依据。一、丙烯酰胺对雄性大鼠生殖功能的影响 8周龄体重(200±10)g健康雄性SD大鼠40只，，随机分成4组，每组10只。灌胃给予丙烯酰胺，剂量为0(对照组)、4、10、18 mg／kg．d，每周染毒6d，共染毒9周。观察动物一般情况、体重以及脏器系数的变化。染毒结束后，测量后肢支撑力，处死大鼠收集睾丸、附睾和血清。测定精子存活率、精子畸形率、睾丸匀浆中碱性磷酸酶(ALP)、酸性磷酸酶(ACP)、乳酸脱氢酶(LDH)和γ-谷氨酰转移酶(γ-GT)活性。结果表明：随着染毒剂量的增加，各剂量组与对照组比较，后肢展开距离显著加宽(P＜0．01)，精子存活率显著下降(P＜0．01)。10 mg／kg．d和18 mg／kg．d剂量组精子畸形率明显上升(P＜0．05)。ACP活性呈下降趋势，ALP活性呈现先上升后下降的趋势，两者的活性在18 mg／kg．d剂量组与对照组比较差异显著(P＜0．05)。LDH活性有下降的趋势，γ-GT活性有上升的趋势，但两者各组间比较差异都不显著(P＞0．05)。二、丙烯酰胺对雄性大鼠脂质过氧化水平的影响染毒结束后，处死大鼠收集睾丸及其他脏器和血清，测定血清和睾丸匀浆中丙二醛(MDA)和还原型谷胱甘肽(GSH)水平以及谷胱甘肽过氧化物酶(GSHPx)和超氧化物歧化酶(SOD)的活性。结果表明：各剂量组与对照组比较，血清中的GSH水平、MDA水平、GSHPx活性和SOD活性，无明显差异(P＞0．05)；而睾丸匀浆中GSH水平和SOD活性显著下降(P＜0．01)，GSHPx活性也显著受到抑制(P＜0．05)，MDA水平无显著差异(P＞0．05)。三、丙烯酰胺对雄性大鼠睾丸生殖内分泌功能的影响染毒结束后，测定血清和睾丸匀浆中睾酮(T)及17β-雌二醇(17β-E_2)浓度。分离纯化睾丸Leydig细胞，建立睾丸Leydig细胞体外原代培养模型。Leydig细胞培养24h后，通过CCK-8法测定各剂量组Leydig细胞活性并测定细胞培养液T浓度。体外丙烯酰胺染毒剂量分为对照(0mmol／L)、0．1、0．75、4、8mmol／L，同样通过CCK-8法观察Leydig细胞活性。结果表明：各染毒剂量组血清和睾丸匀浆中T显著下降(P＜0．05)，17β-E_2水平无明显差异，Leydig细胞活性明显受到抑制(P＜0．01)，细胞培养液T浓度显著降低(P＜0．01)。体外丙烯酰胺染毒24h后，Leydig细胞活性受到显著抑制(P＜0．01)。以上结果表明亚慢性丙烯酰胺染毒损伤雄性生育能力，影响生精过程中有关一些特征酶活性，睾丸是丙烯酰胺毒性作用的重要靶器官，大鼠后肢运动协调性明显受到影响；破坏睾丸氧化-抗氧化系统的平衡，诱导雄性大鼠睾丸氧化损伤的增加，脂质过氧化可能是丙烯酰胺导致睾丸毒性作用的机制之一；影响睾丸Leydig细胞的功能，改变了雄性大鼠体内T／E_2分泌水平，干扰了正常的雄性生殖内分泌功能。
[Abstract]:acrylamide ( acrylamide ) is an important chemical raw material and is an important chemical raw material widely used in drinking water purification , sewage treatment , paper making , mining and scientific research . Effects of acrylamide and acrylamide on the reproductive function of male rats Twenty - eight weeks of age weight ( 200 卤 10 ) g healthy male SD rats were randomly divided into 4 groups . Each group was divided into 4 groups , the dosage was 0 ( control group ) , 4 , 10 , 18 mg / kg 路 d , 6 days a week . ACP activity showed a decreasing trend , ALP activity increased first and then declined , the activity of the two groups was 18 mg / kg 路 d , the difference was significant ( P < 0.05 ) . The activity of LDH decreased and the activity of 纬 - GT increased , but there was no significant difference between the two groups ( P > 0.05 ) . Effect of acrylamide on lipid peroxidation level in male rats The activity of glutathione peroxidase ( MDA ) and glutathione peroxidase ( GSH ) and glutathione peroxidase ( GSHPx ) and superoxide dismutase ( SOD ) in serum and testis homogenate were measured . Effects of acrylamide on reproductive endocrine function in male rat testis The concentration of testosterone ( T ) and 17尾 - estradiol ( 17尾 - E _ 2 ) in serum and testis homogenate were determined after the end of exposure . After 24 h incubation , the activity was determined by CCK - 8 method . The results showed that the concentration of T in serum and testis homogenate decreased significantly ( P < 0 . 05 ) and that of 17 尾 - E _ 2 was significantly inhibited ( P < 0 . 01 ) . After 24 h of acrylamide exposure in vitro , the activity of the cells was significantly inhibited ( P < 0.01 ) . The results showed that the male fertility of subchronic acrylamide was affected by the toxicity of acrylamide , the testis was an important target organ of acrylamide toxicity , and the coordination of rat hindlimb movement was significantly affected . The effect of destroying testis oxidation - antioxidant system was one of the mechanisms to induce testicular toxicity in male rats , and the function of the rat testis was affected . The level of T / E _ 2 secretion in male rats was changed , and the normal male reproductive endocrine function was disturbed .

【学位授予单位】：南京农业大学
【学位级别】：硕士
【学位授予年份】：2007
【分类号】：R363

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