Norton S
Environ Health Perspect. 1978 Oct;26:21-7. doi: 10.1289/ehp.782621.
Both behavior and morphology can be altered by exposure of the CNS to toxic substances. The brain is an organ with considerable structural redundancy and this presumably accounts for some of the ability of the CNS to maintain normal function in the presence of some structural damage. Compensation for damage may also occur through a form of "learning" due to the biochemical and morphological plasticity of the CNS. Examples of these kinds of compensation are enzyme induction and axonal sprouting. Compensatory changes such as these are likely to require days or weeks to develop. On the other hand, short-term, reversible effects of substances such as drugs are not likely to cause morphological changes at doses which affect behavior. The importance of appropriate quantitative data on both morphology and behavior in evaluation of the CNS toxicity of substances is evident.
中枢神经系统暴露于有毒物质会改变行为和形态。大脑是一个具有相当大结构冗余的器官，这大概解释了中枢神经系统在存在一些结构损伤时仍能维持正常功能的部分能力。由于中枢神经系统的生化和形态可塑性，损伤的补偿也可能通过一种“学习”形式发生。这类补偿的例子包括酶诱导和轴突发芽。这种补偿性变化可能需要数天或数周才能形成。另一方面，药物等物质的短期、可逆作用在影响行为的剂量下不太可能引起形态变化。关于形态和行为的适当定量数据在评估物质对中枢神经系统毒性方面的重要性是显而易见的。
