健康报登载的资料：日本研究人员发现自闭症致病机理

kfq87522497

日本滨松医科大学教授铃木胜昭领导的小组在日前出版的美国学术期刊《普通精神病学文献》上报告说，他们利用电子发射计算机断层扫描技术，对20名18岁至33岁自闭症患者和20位正常人脑部进行扫描，结果发现，自闭症患者大脑中负责识别他人表情，被称为梭状回部位的乙酰胆碱含量比正常水平平均低30%，而且，这个含量越低，自闭症越严重。乙酰胆碱在神经细胞的连接处负责传导刺激。

thankstoyilin

类似的研究结论每年都有好多吧。还有用图像模式识别去分析脑白质差异的等等。这都只是特征概括而已。

青山化桥

这个发现给为什么ASD孩子的反应比NT要慢两三拍的现象提供了分子生物学方面的支持依据。不是致病机理。就现在已知的研究结果来看，致病机理不会是单一的，而且我们还离找到答案还有相当一段距离。

沉静

http://www.bbc.co.uk/news/health-12759587

Scientists have shown how a single protein may trigger autistic spectrum disorders by stopping effective communication between brain cells.

The team from Duke University in North Carolina created autistic mice by mutating the gene which controls production of the protein, Shank3.

The animals exhibited social problems, and repetitive behaviour - both classic signs of autism and related conditions.

The Nature study raises hopes of the first effective drug treatments.

Autism is a disorder which, to varying degrees, affects the ability of children and adults to communicate and interact socially.

While hundreds of genes linked to the condition have been found, the precise combination of genetics, biochemistry and other environmental factors which produce autism is still unclear.

Each patient has only one or a handful of those mutations, making it difficult to develop drugs to treat the disorder.

Shank3 is found in the synapses - the junctions between brain cells (neurons) that allow them to communicate with each other.

The researchers created mice which had a mutated form of Shank3, and found that these animals avoided social interactions with other mice.

They also engaged in repetitious and self-injurious grooming behaviour.
Brain circuits

When the MIT team analysed the animals' brains they found defects in the circuits that connect two different areas of the brain, the cortex and the striatum.

Healthy connections between these areas are thought to be key to effective regulation of social behaviours and social interaction.

The researchers say their work underscores just what an important role Shank3 plays in the establishment of circuits in the brain which underlie all our behaviours.

Lead researcher Dr Guoping Feng said: "Our study demonstrated that Shank3 mutation in mice lead to defects in neuron-neuron communications.

"These findings and the mouse model now allow us to figure out the precise neural circuit defects responsible for these abnormal behaviours, which could lead to novel strategies and targets for developing treatment."

It is thought that only a small percentage of people with autism have mutations in Shank3, but Dr Feng believes many other cases may be linked to disruptions to other proteins that control synaptic function.

If true he believes it should be possible to develop treatments that restore synaptic function, regardless of which protein is defective in a specific individual.

Carol Povey, director of the National Autistic Society's Centre for Autism, said: "Animal research can help advance our understanding or the role of genetics and their influence on behaviour, however it is only a small part of the picture when it comes to understanding autism.

"Human brains are far more complex than those of other mammals, and it is believed that a variety of factors are responsible for the development of the condition."