化学和电突触之间的差异

Key Difference – Chemical vs Electrical Synapse

Chemical and electrical synapses are specialized biological structures found in the nervous system; they connectneuronstogether and transmit signals across the neurons. The key difference between chemical and electrical synapse is their method of transmitting signals;chemical synapse pass signals in the form of chemical molecules called neurotransmitters while electrical synapse transmits signals in the form of electrical signals without the use of molecules.化学突触和电突触的结构由于作用方式而彼此略有不同。

内容
1.Overview and Key Difference
2.什么是突触
3.什么是化学突触
4.What is Electrical Synapse
5.Side by Side Comparison – Chemical vs Electrical Synapse
6。概括

什么是突触？

A synapse can be defined as a structure mediating the transmission of signals from oneneuron到相邻的神经元。在神经系统中发现突触。它们可以传输电信号或化学信号。可以根据这种类型的信号将突触分为两种主要类型：电突触和化学突触。在突触中，交流两个神经元的近距离质膜to pass the signal accurately and efficiently. The neuron which sends the signal consists of the presynaptic end while the neuron receiving the signal consists of the postsynaptic end. These ends can be seen inaxon and dendrite/soma respectively.

什么是化学突触?

Chemical synapse is a biological structure that can be found among two neurons or among a neuron and a nonneuronal cell and its main function is to communicate with each other via chemical messengers as shown in figure 01. These chemical messengers are known asneurotransmitters。Neurotransmitters are produced and packaged inside the smallvesicles称为突触囊泡。突触囊泡充满神经递质，并在突触前神经元的突触前末端积聚。当作用电位变化在突触前神经元膜中时，这些神经递质会被释放胞吞作用to a space calledsynaptic cleft。Once these neurotransmitters enter into the synaptic cleft, they bind with the specific receptors located on the surface of the postsynaptic neuron and give the information. This is the type of chemical signal transmission that occurs at the chemical synapse; thus, these structures are of utmost importance to connect the nervous system without collapse. Signal transmission through chemical synapse occurs in only one direction.

One organism contains a huge number of chemical synapse in its nervous system. An adult may have 1000 to 5000 trillion chemical synapses in the central nervous system. This number can vary with the age.

什么是电气突触？

电气突触是一种结构，该结构促进了两个神经元通过电信号彼此通信的情况，而无需任何化学参与。在电气突触中，突触前神经元膜和突触后神经元膜彼此之间非常接近，并通过制作一个称为GAP连接的通道，如图2所示。然后是离子电流形式的信号，流过间隙连接被动地允许信号传输。使用称为连接子的蛋白质通道形成间隙连接。连接子是管状蛋白，可以通过两个神经元通过。

What is the difference between Chemical and Electrical Synapse?

化学与电突触
In chemical synapse, signal transmission happens through chemical molecules called neurotransmitters.	在电气突触中，信号传输以电信号的形式发生，而无需使用分子。
Modification of Signals
Signals are modified during the transmission.	传输过程中未修改信号。
Release of Signals
Neurotransmitters are released by exocytosis and diffused in the synapsis cleft and then are bound to receptors.	Electric signal pass via gap junctions.
两个神经元之间的空间
Space between the pre and postsynaptic ends is larger.	Space between the pre and postsynaptic ends is very small.
Direction of Signal
Signal transmission happens only into one direction.	Signal transmission can happen in both directions.
能源消耗
Signal transmission requires energy. So it’s an active process.	信号传输发生而无需使用能量。因此，这是一个被动过程。
Speed of Transmission
Signal transmission happens at a moderate speed.	Signal transmission is extremely fast.

摘要 - 化学与电突触

There are two main types of synapses called chemical and electrical synapses. Chemical synapse uses chemicals called neurotransmitters to transmit signals along the neurons and facilitates a unidirectional transmission. Electrical synapse uses an ionic current to transmit signals along the neurons and facilitates transmission in both directions. The space between two neurons in the chemical synapse is larger and is known as synaptic cleft. Neurotransmitters are diffused in the synaptic cleft till they find their specific receptors. Two neurons in the electric synapse physically connect with each other through gap junctions; hence, the space is very small.

Reference:
1. Purves, Dale. “Chemical Synapses.”Neuroscience。第二版。美国国家医学图书馆，1970年1月1日。2017年2月6日
2.Purves, Dale. “Electrical Synapses.”Neuroscience。第二版。美国国家医学图书馆，1970年1月1日。2017年2月6日
3. Nicholls，J。G.和D. Purves。“在水ech的中枢神经系统中，单个感觉细胞与运动神经元之间的化学和电突触传播的比较。”The Journal of Physiology。U.S. National Library of Medicine, Sept. 1972. Web. 06 Feb. 2017

Image Courtesy:
1.“ 1225化学突触”OpenStax–（CC由4.0）viaCommons Wikimedia
2. Mariana Ruiz Ladyofhats的“ Connexon和Connexin结构” - （公共领域）Commons Wikimedia