Studies were carried out on the liver and intestine tissue of Clarias gariepinus after exposure to sublethal concentrations of LC₅₀ lead nitrate for 20 days. Fish were distributed into four groups, control (0 mg/L, LC₅₀ of Pb(NO₃)₂) and three groups exposed to 20, 40 and 60% of the LC₅₀ of Pb(NO₃)₂ (16.12, 32.24 and 48.37 mg/L respectively). Section of hepatic and intestine tissues showed the normal structure for control group. However, treated hepatic tissues of fish exhibited altered its characteristic architecture, with remarkably high vacuolation in hepatocytes and hepatoctolysis. Also, central vein was dilated and increased hemorrhage in the sections of almost samples from treated fish. Increased number of fibroblasts and Kuppffer cells were observed in the examined sections from treated fish when compared to the control. Therefore, fish treated with 60% LD₅₀ of Pb(NO₃)₂ observed the proliferation of fibrous in connective tissue particularly near sinusoids and substituting liver parenchyma. Therefore, intestinal sections from the different treated fish groups revealed an evident harmful to intestinal tissue, especially in enterocytes and structures of villi. Also, disturbed longitudinal and circular muscularis were observed, to abnormally dilated, lamina propria, was infiltrated with a huge numbers of inflammatory leukocytes. Mucous secreting goblet cells proliferated and multiplied in all exposed fish.

中文翻译：

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亚硝酸铅暴露于致死浓度的非洲Cat鱼Clarias gariepinus肝脏和肠道的组织病理学改变

在亚致死浓度的LC ₅₀硝酸铅中暴露20天后，对Clarias gariepinus的肝脏和肠组织进行了研究。将鱼分为四组，即对照组（0 mg / L，Pb（NO ₃）_2的LC ₅₀），三组暴露于Pb（NO ₃）₂的LC ₅₀的20％，40％和60％（分别为16.12、32.24和48.37 mg / L）。对照组肝，肠组织切片显示正常。然而，经过处理的鱼肝组织表现出其特征性结构的改变，肝细胞的空泡化和肝细胞溶解显着增加。而且，在经过处理的鱼的几乎所有样品的切片中，中心静脉都扩张了，出血增加了。与对照相比，在处理过的鱼的检查切片中观察到成纤维细胞和Kuppffer细胞数量增加。因此，用60％LD ₅₀的Pb（NO ₃）₂处理的鱼观察到结缔组织中纤维的增生，尤其是在正弦曲线附近并取代了肝实质。因此，来自不同处理鱼群的肠段显示出明显对肠组织有害，特别是在肠上皮细胞和绒毛结构中。另外，观察到纵向和圆形肌层紊乱，异常扩张的固有层被大量炎性白细胞浸润。粘液分泌杯状细胞在所有裸露的鱼类中增殖并繁殖。