镉对鲫鱼消化道内分泌细胞密度的影响
发布时间：2018-12-25 11:06
【摘要】：重金属污染不仅影响工农业的生产,而且可以通过食物链的富集作用,蓄积到人体内,对人类健康造成严重的危害。镉是一种主要蓄积在肺脏、肝脏、肾脏、骨骼、生殖系统和免疫系统中的有毒污染物,其对组织的毒性主要包括肾毒性、致癌、致畸和内分泌干扰。本研究首先分析了汉江汉中段鲤鱼、青鱼、泥鳅、鲫鱼、生鱼、鲶鱼、鲢鱼7种淡水鱼肝、鳃和肌肉中镉的分布。然后在实验条件下,以镉作为实验用毒,以鲫鱼作为实验动物,使用静态染毒法进行毒理学实验。共设置3组镉浓度梯度,1个空白对照组,每组设置两组平行实验。染毒10 d后,采用H·E染色法和SABC免疫组化染色法探讨了鲫鱼的消化道组织学与消化道内分泌细胞密度变化。结果表明,汉江汉中段常见7种淡水鱼中,检测的3种器官中,平均镉含量分布顺序由高到低是肝脏鳃肌肉。其中7种鱼的鳃和肝脏中镉含量都超标,但肌肉中镉含量较低,仅泥鳅和鲤超出标准。组织学观察显示,鲫鱼肠道由内到外可分为4层,分别是粘膜层、粘膜下层、肌层和外膜层,组织学结构上染毒组与空白组没有显著差异。免疫组化结果显示,胃泌素细胞、生长抑素细胞、血管活性肠肽细胞在鲫鱼整个肠道中都有分布,胃泌素细胞和生长抑素细胞的密度由前肠到后肠递减,在不同部位的密度达到了显著差异。血管活性肠肽细胞的分布规律与胃泌素细胞和生长抑素细胞类似,但各肠段密度上没有显著差异。P物质细胞仅在中肠分布,促胰液素细胞仅分布在前肠。在镉暴露10d之后,鲫鱼肠道组织学结构没有明显变化,但消化道内分泌细胞的密度发生了变化。随着染毒镉浓度的增加,胃泌素细胞、血管活性肠肽细胞的密度呈上升趋势;生长抑素、P物质、促胰液素细胞的密度呈下降趋势。与对照组相比,胃泌素细胞密度的上升在前肠和中肠有显著性差异,血管活性肠肽细胞密度的上升仅在后肠有显著性差异,而生长抑素细胞密度的下降仅在前肠差异显著。P物质细胞和促胰液素细胞的密度下降都达到了显著性差异。通过讨论,得出下列结论:汉江汉中段淡水鱼有一定程度的镉蓄积现象,并且部分鱼肌肉镉含量超标,不可食用。水环境镉浓度在5.00 mg/L以内时,10 d的镉暴露对鲫鱼消化道没有造成显著的组织学损伤,但造成了鲫鱼消化道内分泌细胞的分布密度改变。水中镉浓度与消化道内分泌细胞密度呈显著相关关系。镉对消化道内分泌细胞的影响受多种机制调控,不仅与镉的肾毒性、肝毒性有关,也与内分泌细胞间相互的调控有关。
[Abstract]:Heavy metal pollution not only affects the production of industry and agriculture, but also accumulates into human body through the enrichment of food chain, which causes serious harm to human health. Cadmium is a toxic pollutant mainly accumulated in lung, liver, kidney, skeleton, reproductive system and immune system. Its toxicity to tissues mainly includes nephrotoxicity, carcinogenesis, teratogenicity and endocrine disruptions. The distribution of cadmium in liver, gills and muscles of Carp, herring fish, Loach, Carassius auratus, Raw fish, catfish and silver carp in Hanzhong section of Hanjiang River was analyzed. Under the experimental conditions, cadmium was used as experimental poison and crucian carp as experimental animal. Three groups of cadmium concentration gradient, one blank control group, two groups of parallel experiments were set up in each group. After 10 days of exposure, the changes of digestive tract histology and endocrine cell density of crucian carp were studied by H E staining and SABC immunohistochemical staining. The results showed that the average cadmium content in the three organs of 7 freshwater fishes in Hanzhong section of Hanjiang River was liver Gill muscle from high to low. The contents of cadmium in Gill and liver of 7 species of fish were above the standard, but the content of cadmium in muscle was lower, only Loach and common carp exceeded the standard. Histological observation showed that the intestinal tract of Carassius auratus could be divided into four layers from inside to outside, which were mucosal layer, submucosal layer, muscular layer and outer membrane layer. There was no significant difference in histologically and structurally between exposed group and blank group. Immunohistochemical results showed that gastrin cells, somatostatin cells and vasoactive intestinal peptide cells were distributed in the whole intestine of crucian carp, and the density of gastrin cells and somatostatin cells decreased from foregut to hindgut. There were significant differences in density between different parts. The distribution of vasoactive intestinal peptide cells was similar to that of gastrin cells and somatostatin cells, but there was no significant difference in the density of each intestinal segment. After 10 days of cadmium exposure, the intestinal histological structure of crucian carp did not change significantly, but the density of endocrine cells in digestive tract changed. With the increase of cadmium concentration, the density of gastrin cells and vasoactive intestinal peptide cells increased, and the density of somatostatin, substance P and trypsin cells decreased. Compared with the control group, the increase of gastrin cell density was significant in the foregut and midgut, while the increase of vasoactive intestinal peptide cell density was only significant in the hindgut. However, the decrease of somatostatin cell density was only significant in the foregut. Through discussion, the following conclusions are drawn: fresh water fish in the middle section of Han Jianghan have a certain degree of cadmium accumulation, and some of the fish muscle cadmium content exceeds the standard, so it is not edible. When the concentration of cadmium in water was less than 5.00 mg/L, cadmium exposure for 10 days did not cause significant histological damage to the digestive tract of crucian carp, but resulted in the change of distribution density of endocrine cells in digestive tract of crucian carp. There was a significant correlation between the concentration of cadmium and the density of endocrine cells in digestive tract. The effects of cadmium on endocrine cells in digestive tract are regulated by many mechanisms, not only related to the nephrotoxicity and hepatotoxicity of cadmium, but also to the regulation of endocrine cells.
【学位授予单位】：陕西理工学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S917.4;X503.225
本文编号：2391073
[Abstract]:Heavy metal pollution not only affects the production of industry and agriculture, but also accumulates into human body through the enrichment of food chain, which causes serious harm to human health. Cadmium is a toxic pollutant mainly accumulated in lung, liver, kidney, skeleton, reproductive system and immune system. Its toxicity to tissues mainly includes nephrotoxicity, carcinogenesis, teratogenicity and endocrine disruptions. The distribution of cadmium in liver, gills and muscles of Carp, herring fish, Loach, Carassius auratus, Raw fish, catfish and silver carp in Hanzhong section of Hanjiang River was analyzed. Under the experimental conditions, cadmium was used as experimental poison and crucian carp as experimental animal. Three groups of cadmium concentration gradient, one blank control group, two groups of parallel experiments were set up in each group. After 10 days of exposure, the changes of digestive tract histology and endocrine cell density of crucian carp were studied by H E staining and SABC immunohistochemical staining. The results showed that the average cadmium content in the three organs of 7 freshwater fishes in Hanzhong section of Hanjiang River was liver Gill muscle from high to low. The contents of cadmium in Gill and liver of 7 species of fish were above the standard, but the content of cadmium in muscle was lower, only Loach and common carp exceeded the standard. Histological observation showed that the intestinal tract of Carassius auratus could be divided into four layers from inside to outside, which were mucosal layer, submucosal layer, muscular layer and outer membrane layer. There was no significant difference in histologically and structurally between exposed group and blank group. Immunohistochemical results showed that gastrin cells, somatostatin cells and vasoactive intestinal peptide cells were distributed in the whole intestine of crucian carp, and the density of gastrin cells and somatostatin cells decreased from foregut to hindgut. There were significant differences in density between different parts. The distribution of vasoactive intestinal peptide cells was similar to that of gastrin cells and somatostatin cells, but there was no significant difference in the density of each intestinal segment. After 10 days of cadmium exposure, the intestinal histological structure of crucian carp did not change significantly, but the density of endocrine cells in digestive tract changed. With the increase of cadmium concentration, the density of gastrin cells and vasoactive intestinal peptide cells increased, and the density of somatostatin, substance P and trypsin cells decreased. Compared with the control group, the increase of gastrin cell density was significant in the foregut and midgut, while the increase of vasoactive intestinal peptide cell density was only significant in the hindgut. However, the decrease of somatostatin cell density was only significant in the foregut. Through discussion, the following conclusions are drawn: fresh water fish in the middle section of Han Jianghan have a certain degree of cadmium accumulation, and some of the fish muscle cadmium content exceeds the standard, so it is not edible. When the concentration of cadmium in water was less than 5.00 mg/L, cadmium exposure for 10 days did not cause significant histological damage to the digestive tract of crucian carp, but resulted in the change of distribution density of endocrine cells in digestive tract of crucian carp. There was a significant correlation between the concentration of cadmium and the density of endocrine cells in digestive tract. The effects of cadmium on endocrine cells in digestive tract are regulated by many mechanisms, not only related to the nephrotoxicity and hepatotoxicity of cadmium, but also to the regulation of endocrine cells.
【学位授予单位】：陕西理工学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S917.4;X503.225
【参考文献】
相关期刊论文 前2条
1 张春岭;卓丽玲;;枣庄市中区鲫鱼重金属含量及其安全评价[J];山东畜牧兽医;2010年09期
2 朴英杰;胃肠内分泌细胞[J];第一军医大学学报;1986年02期
，本文编号：2391073
本文链接：https://www.wllwen.com/shoufeilunwen/zaizhiyanjiusheng/2391073.html
