Relationship between transmitter release and presynaptic calcium influx when calcium enters through discrete channels.
Relationship between transmitter release and presynaptic calcium influx when calcium enters through discrete channels.
复制标题
当钙通过离散通道进入时，递质释放与突触前钙流入之间的关系。
DOI：
10.1073/pnas.83.9.3032
复制
发表时间：
1986
影响因子：
11.1
通讯作者：
Fogelson,AL
中科院分区：
文献类型：
--
作者：
Zucker,RS;Fogelson,AL
我们已经使用了一个三维扩散模型的钙进入突触前神经末梢通过离散通道来模拟实验相关的递质释放突触前钙电流。如果钙通道被很好地分离，则该关系将小于线性，或者将向下弯曲。它将类似于幂律函数，其指数小于钙作用的协同性，如果通道更紧密地聚集在一起。大突触前去极化引起更多的释放比小去极化承认相同的钙内流。这是因为大脉冲打开更多彼此靠近的通道，结果是由于从相邻通道扩散的钙的重叠，释放位点附近的钙浓度更大。
We have used a three-dimensional diffusion model of calcium entering the presynaptic nerve terminal through discrete channels to simulate experiments relating transmitter release to presynaptic calcium current. The relationship will be less than linear, or will curve downward, if calcium channels are well separated. It will resemble a power-law function with exponent less than the cooperativity of calcium action if channels are clustered closer together. Large presynaptic depolarizations elicit more release than small depolarizations admitting the same calcium influx. This occurs because large pulses open more channels near each other, with the result that the calcium concentration near release sites is greater, due to overlap of calcium diffusing from adjacent channels.