慢性铝染毒大鼠脑及其雌激素受体的变化

Changes of both brain tissue and its estrogen receptors in chronic aluminum-poi soning rats

目的 探讨慢性铝染毒对大鼠端脑皮质和海马组织细胞、雌激素受体亚型表达及血清雌激素水平的影响 ,比较上述变化与阿尔茨海默病病变的相似性。方法 用长期腹腔注射AlCl3 溶液使大鼠染毒 ,用放射免疫法测定血清雌二醇水平 ,用HE染色和免疫组化观察大鼠端脑和海马组织细胞结构及雌激素受体亚型的表达。结果 慢性铝染毒大鼠血清雌二醇水平降低到 (7 67± 1 80 )pg ml(P <0 0 0 0 1 ) ,端脑皮质和海马出现神经细胞水肿 ,卫星增多现象 ,胶质细胞增多 ,噬神经元现象和神经元丢失 ;海马神经细胞排列紊乱 ,层数和神经细胞数目减少 ,CA3 CA4区神经细胞脱失 ,胶质细胞浸润。ERα和ERβ免疫阳性颗粒普遍存在于正常大鼠端脑皮质Ⅱ～Ⅵ层神经细胞内 ,ERα免疫阳性颗粒存在于细胞核、ERβ免疫阳性颗粒存在于胞浆。慢性铝染毒后 ,端脑皮质ERα免疫阳性神经细胞数量明显减少 ,多数神经细胞内ERα的表达降低或呈阴性 ;端脑皮质中ERβ免疫阳性神经细胞数量变化不明显 ,但表达量增强。结论 慢性铝染毒可以导致端脑皮质和海马神经细胞损伤丢失 ,端脑皮质雌激素受体亚型表达量异常 ,血液雌激素水平降低。

Objective To investigate the effects of aluminum on serum estrodial(E\-2),structural changes of both cerebral c orti ce and hippocampus as well as estrogen receptors α and β(ERα,ERβ)expression were determined.Methods Rats administrated with aluminum chloride by intraperi toneal in jection.Serum E\-2 were tested by radioimmunoassay.Cerebral cortex and hippocamp i were examined using histochemistry.Expression of both ERα and ERβ were teste d by histoimmunoassay.Results Chronic aluminum exposure decreased serum E\-2 to 7\^67 ±1\80 pg/ml(P<0 0001),induced neurons swelling,glia satellitism,phagoneur onism,reactive glial cells aggregation and neuron loss in both cerebral cortex and hippocampi.Besides,neuron lamian disorganized and neurons seriously l ost in CA3/CA4 regions of hippocampus were observed in Aluminum-treated rats.ER α expressed in the nuclei and ERβ in the cytoplasma of both neurons and glial cells in Ⅱ～Ⅵ lamina of cerebral cortex.Chronic Aluminum poisoning decreased E Rα expression and increased ERβ expression significantly in cerebral cortice.Conclusion Chronic Aluminum administration significantly decreased serum E\-2,induced inflammation and neuron loss in both cerebral cortex and hipp ocampi,down-regulated ERα expression and up-regulated ERβ expression in cere b ral cortex.The changes were some similar to the pathological manifestation of hu man Alzheimer's disease.