燃煤型氟中毒大鼠海马区组织病理学分析

Histopathological changes in hippocampal CA1 area of rats with coal burning fluorosis

目的复制燃煤型氟中毒大鼠模型并观察其对海马CA1区形态学影响。方法 24只SD大鼠随机分为3组,对照组、低、高氟组;染氟组以地氟病区燃煤烘烤的玉米为主要饲料,复制氟中毒动物模型,6个月后用氟离子选择电极法检测动物尿、骨及脑氟含量,观察大鼠海马CA1区神经元病理变化,用Biomias 2000图象分析系统测试大鼠海马CA1区神经元胞体平均面积、周长及平均灰度值。结果低、高氟组大鼠尿氟为(2.87±0.12)、(5.27±0.15)mg/L,骨氟(2 912±140)、(4 624±20)mg/kg,脑氟(1.14±0.04)、(1.79±0.04)mg/kg;与对照组尿氟(1.68±0.02)mg/L、骨氟(1479±127)mg/kg、脑氟(0.52±0.05)mg/kg比较,差异有统计学意义(P<0.05或P<0.01);尼氏染色显示,与对照组大鼠神经元平均灰度值(115±4)比较,染氟组大鼠均明显增加[低氟(157±7),高氟(164±8)]。结论长期食用燃煤型氟中毒病区燃煤烘烤的粮食可以引起氟中毒;并导致动物尿、骨、脑氟含量增高,使大鼠海马CA1区神经元蛋白合成功能下降。

Objective To duplicate the animal model with coal burning fluorosis and to observe its influence on the histopathology in the hippocampal CA1 area in rats. Methods Twenty-four SD rats were randomly divided into control, low-fluoride, and high-fluoride exposed groups. Low- and high-fluoride exposed groups were fed with the corn polluted in drying processes with burning coal containing high level of fluoride from the endemic fluorosis area to produce the animal model of fluorosis. During the sixth month experiment, fluoride contents in urine, bone and brain of the rats were detected with fluorine ion selective electrode ,and neuro-pathological changes of the hippocampal CAI area of the rats were examined with hematoxylin-eosin and Nissl＇s staining and analyzed by Biomias 2000 Imaging Analysis System. Results Compared with those of the control group（ 1.68 ± 0.02 mg/L, 1 479 ± 127,0. 52 ± 0. 05 mg/kg of fluoride contents in urine, bone, and brain tissue） ,the fluoride contents in urine（2. 87 ±0. 12,5.27 ±0. 15 mg/L） ,bone（2 912 ± 140,4 624 ±20 mg/kg） ,and brain tissues（ 1.14 ±0.04,1.79± 0.04 mg/kg） of the rats with fluorosis were increased markedly with significant differences （ P 〈 0.05 or 0. 01 for all）. The average grey values of neurons in the hippocampal CA1 of the rats were significantly increased in low-fluoride（ 157 ± 7 ） and high-fluoride（ 164 ± 8 ） exposed groups compared to those of the control（ 115 ± 4 ）. Conclusion Chronic fluorosis could be induced by feeding with corn polluted with high level of fluoride and the fluorosis can decrease protein synthesis in neurons of brains in rats.