速い興奮性神経伝達はイオンチャネル型グルタミン酸受容体

Information transmission in the brain is、Neurotransmitters released from axons of nerve cells (presynaptic)、It begins to bind to neurotransmitter receptors present dendrites or cell bodies of other neurons attached at synapses (postsynaptic)。There are a variety of neurotransmitters, which is said to more than 1,000 types of in the brain、inside that、I to talk is、It is glutamic acid and its receptor。
Generally the neurotransmitter receptors、There is a metabolic type and ion channel type。Metabotropic receptors、It tells signal by biochemical response of bound intracellularly mediators。On the other hand、Ionotropic receptors、Is opened ion channel conformation is changed when bound to transmitter、Convey information by flowing such as sodium ions and calcium ions into neurons。And involving ion channel type to fast information transmission of this order of milliseconds。Metabolism form of the receptor is considered to have been used to adjust the fast information transmission。
It is mainly ionotropic glutamate receptors to play a fast excitatory neurotransmission in the vertebrate。Glutamic acid is a non-essential amino acid that is abundantly synthesized in the body、Due to the presence anywhere too、Is the second half of the 20th century had established itself as a neurotransmitter。Glutamate receptors are the most important protein controlling the synaptic transmission and plasticity。

Increase or decrease in the short and medium-term storage and the AMPA receptors,,ja,There are also several sub-type of ion channel-type glutamate receptor. Fast neurotransmission mainly AMPA (Anpa,,ja

There are also several sub-type of ion channel-type glutamate receptor。Fast neurotransmission mainly AMPA (Anpa:α- amino-3-hydroxy-5-Mesookisazoru 4 propionic acid) receptor is responsible。Synaptic plasticity responsible for the storage of short and medium-term, such as LTP and LTD is、Increase or decrease in the number of AMPA receptors has become clear in the study of ever it is the entity in the synapse。
Cerebrum、cerebellum、Feeling in various brain regions of the central nervous system such as spinal cord、Cognitive、The responsible for the fast information transmission of essential milliseconds, such as exercise、Open fast ion channel、There is only AMPA receptors can quickly closed。In order to elucidate the formation mechanism of the memory of the short and medium term is、Or increase in the how the number of AMPA receptors in the synaptic、That is why it is essential to understand whether or reduced。

Detailed mechanisms incorporate the receptor into the cell,,ja,As one of the results of our research, when the LTD is the synaptic plasticity of short and medium-term occurs, how the AMPA receptors in the synapse was revealed whether to decrease.,,ja

As one of the outcomes of our research、When the LTD occurs is the synaptic plasticity of short and medium-term、How AMPA receptors in the synapse was revealed whether to decrease。
AMPA receptors in the synaptic、Stable and exists in a state of being embedded in the cell membrane。It is an image, such as a tightly bearded was radish roots in the field。It is accompanied by a serious effort withdraw it from the ground in order to reduce the number of AMPA receptors。In fact captures the cell membrane by AMPA receptors in a cell in the state that AMPA receptor is stuck in the cell membrane。Also it makes it easy to increase the number of AMPA receptors again depending on the neural activity In this way。
To form the vesicles a part of the cell membrane is invaginated into a cell、In many cases has been found that clathrin is a molecule that round the cell membrane (clathrin) is required。Structure lattice-like (clathrate) because、This is the name that comes with。You need clathrin adapter protein AP2 (adaptor protein) in order to integrate the class of phosphorus in the synaptic。We are、Using neurons mouse hippocampus (brain regions storing a relationship is deep)、By intracellular calcium raised when given a stimulus that induces LTD first reveals possible to integrate AP2 and clathrin by lipid that phosphatidylinositol 4,5 diphosphate (PIP2) is synthesized in the synaptic sites Did。That is the activity of an enzyme to synthesize PIP2 is controlled by neural activity、That is why it was found is one of the key to controlling storage。

AP2 is selected transport the AMPA receptor through the star Gay Jin,ja

Now when the LTD to occur、AMPA receptor only will be incorporated into the cell。But how to sort the AMPA receptor from a variety of proteins present on the cell surface did not know。We are、Again using the hippocampal nerve cells of mice、By adapter protein AP2 binds to a protein called star Gay Jin is a subunit of the AMPA receptor、Only indirectly AMPA receptor was discovered that incorporate the transport vesicles。Because Star gay Jin、It is a strange name, but、It comes from (star Gay Jin) attitude, such as looking at the stars when the mouse caused the epileptic seizures。
After all、By neural activity to induce LTD、AP2 by lipids are synthesized that PIP2 is to bend the cell membrane to the inside by clathrin increased in synaptic。Further AP2 is by binding a star gay Jin is a subunit of the AMPA receptor、The AMPA receptor selectively collected has been found that the mechanism that incorporated into the cell。It is complicated but、To ensure the information transmission、I think that it is a mechanism for that, not to mistake。
Abnormality of the synapse can cause a variety of diseases。AMPA receptor is also thought to be involved in dementia and neurodegenerative diseases。So elucidation of the detailed mechanism of transport control of such AMPA receptor is an important factor leading to such as drug discovery。As a drug discovery target、Than the AMPA receptor itself、Perhaps it might be best if we try and focus on the star Gay Jin。 <2016.03>

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