调查发现稀土元素可以损害儿童的认知功能,实验发现稀土元素对动物的神经系统有不利反应.但是损害机制并不清楚,通常选择氯化镧来研究稀土元素的作用.在本研究中我们的主要目的是研究LaCl3诱导的记忆损伤、CREB信号途径的局部表达的可能机制以及海马体突触的超显微结构.泌乳期大鼠分别用0, 0.25%, 0.50%, 和1.0% LaCl3饮水处理一个月.结果发现0.25%, 0.50%, 和1.0% LaCl3能够显著的损害幼鼠的记忆.在LaCl3处理后,海马体中pCaMK IV, pMAPK, pCREB, c-fos and egr1的表达严重下调,同时海马体的超显微结构也受损.这些结果表明：LaCl3能够损伤大鼠的记忆,可能是通过pCaMK IV, pMAPK, pCREB, c-fos and egr1的低水平表达和改变海马体的超显微结构老实现的.

  Toxicol Lett. 2009 Jul 27. [Epub ahead of print] Links
  Lanthanum Chloride Impairs Memory, Decreases pCaMK IV, pMAPK and pCREB Expression of Hippocampus in Rats.
  Yang J, Liu Q, Zhang L, Wu S, Qi M, Lu S, Xi Q, Cai Y.
  Department of Toxicology, School of Public Health, China Medical University, 92 North 2nd Road, Shenyang 110001, PR China.
  Surveys have reported that rare-earth elements (REEs) could impair cognitive functions of children. Experimental studies have shown the neurological adverse effects of REEs on animals. However, the mechanism underlying these impairments is unclear. Lanthanum is often selected to study the effects of REEs. The purpose of this study was to investigate the memory impairment induced by lanthanum chloride (LaCl3) exposure and the possible mechanism from the aspects of expression of CREB signal pathway and synaptic ultra-structure in the hippocampus. Lactational rats were exposed to 0, 0.25%, 0.50%, and 1.0% LaCl3 in drinking water, respectively. Their offspring were exposed to LaCl3 by parental lactation for 3 weeks and then administrated with 0, 0.25%, 0.50% and 1.0% LaCl3 in drinking water for 1 month. The results showed that 0.25%, 0.50%, and 1.0% LaCl3 exposure could significantly impair memory of young rats. Hippocampal pCaMK IV, pMAPK, pCREB, c-fos and egr1 expression were decreased significantly, and synaptic ultra-structure was negatively affected after LaCl3 exposure. These results indicate that LaCl3 exposure impairs memory of rats and this impairment may be attributed to the lower levels of pCaMK IV, pMAPK, pCREB, c-fos and egr1 expression and change of synaptic ultra-structure in hippocampus.

相关阅读
DNA甲基转移酶的表达调控及主要生物学功能
植物叶绿体基因组基因表达调控的研究
pET-28a原核不能表达目的蛋白