Relation between the dynamics of trace elements and the aging mechanism of the brain

在本研究中，我们试图评估脑中微量元素随衰老的动态变化，并通过分析和生化研究阐明微量元素在脑衰老机制中的作用。研究结果如下：1.脑内微量元素分析新方法的建立1)建立了用电感耦合等离子体质谱同时测定脑中微量元素的多重分析方法。2)建立了分离大鼠脑区富含突触体组分的方法，并测定了这些组分中的微量元素含量。3)建立了用脑微透析法测定突触中微量元素释放水平的方法。4)建立了一种新的分离大鼠脑区神经元和神经胶质细胞组分的方法，并测定了这些组分中的微量元素浓度。微量元素和…变化的阐明随着大脑的老化，更多的神经递质1)我们测定了人和大鼠大脑不同区域的微量元素浓度随年龄的变化。在人脑的大部分区域，年龄与K、Rb呈显著负相关，与Cd、Sn呈显著正相关。随着年龄的增长，大鼠大脑的7个区域的Rb浓度也显著下降。2)测定了衰老加速小鼠(SAM)脑内微量元素和神经递质的增龄变化。SAM-P10表现为脑内微量元素代谢异常，神经递质代谢异常。这些结果提示，微量元素可能在衰老的调节中起着重要作用。3)测定遗传性铜代谢异常LEC大鼠脑内微量元素和神经递质浓度随增龄的变化。观察到LEC大鼠脑内微量元素和神经递质代谢随年龄的变化。较少

In the present study, we intended to evaluate the dynamics of brain trace elements with aging and to elucidate roles of trace elements in the aging mechanism of the brain from analytical and biochemical investigations. Results obtained in the present investigations are as follows ;1. Development of new analytical methods to investigate trace elements in the brain1) We established the simultaneous multi-analytical procedure to determine trace elements by ICP-MS spectrometry in the brain. 2) We developed a method to separate synaptosomal fractions (rich in pre-syn-apse) in the rat brain regions, and trace element concentrations were determined in those fractions. 3) We developed a method to determine the release levels of trace elements from synapse using brain microdialysis. 4) We developed a new method to separate neuronal and glial cell fractions in the rat brain regions, and trace element concentrations were determined in those fractions.2. Elucidation of changes in trace elements an … More d neurotransmitters with aging of the brain1) We determined changes in trace element concentrations by aging in discrete regions of human and rat brains. Significant negative correlations between age and K or Rb and significant positive correlations between age and Cd or Sn were found in most regions of the human brain. Significant decreases in Rb concentrations by aging were also observed in 7 regions of the rat brain. 2) We determined changes in concentrations of trace elements and neurotransmitters by aging in the brain of senescence accelerated mice (SAM). An abnormal metabolism of brain trace elements as well as that of neurotransmitters was observed in SAM-P10. These results suggest that trace elements may play an important roles in regulation of aging. 3) We determined changes in concentrations of trace elements and neurotransmitters by aging in the brain of LEC rats with hereditary abnormal Cu metabolism. Age-dependent changes in the metabolism of trace elements and neurotransmitters were observed in the LEC rat brain. Less