The Performance of Synapses That Convey Discrete Graded Potentials in an Insect Visual Pathway
The Performance of Synapses That Convey Discrete Graded Potentials in an Insect Visual Pathway
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昆虫视觉通路中传递离散分级电位的突触的性能
DOI：
10.1523/jneurosci.19-23-10584.1999
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
P. Simmons
中科院分区：
文献类型：
--
作者：
P. Simmons
来自非尖峰神经元的突触传递微小的渐变电位，但其突触后电位幅度的变异性还没有得到广泛的研究。在突触前信号是全有或无峰的突触，神经递质释放的概率方式导致突触后电位的幅度变化。我测量了在蝗虫耳廓系统中被识别的两对大型二级神经元之间传递小梯度电位的突触操作的可靠性。IPSP是由突触前神经元中的小的反弹峰介导的，这些峰的幅度是渐变的。绘制的尖峰幅度对IPSP幅度的转换曲线具有典型的S形状，其中心为线性段，其中IPSP幅度在−0.2~−0.6之间，与尖峰幅度一样大，但表现出明显的散射。大约一半的散射可归因于背景噪声，其中大部分起源于光感受器并持续在黑暗中。剩余的噪声是突触本身固有的，通常是0.3-0.7 mV的幅度。它将区分两个尖峰幅度的分辨率限制在∼2 mV，而且由于传递曲线的线性部分在尖峰幅度上占据∼10 mV，因此可以通过突触传递的离散信号电平的数量限制在大约5个。噪声的幅度在突触工作范围内是恒定的，这意味着突触前膜电位不太可能通过为量子释放设置单一的概率水平来控制递质的释放。
Synapses from nonspiking neurons transmit small graded changes in potential, but variability in their postsynaptic potential amplitudes has not been extensively studied. At synapses where the presynaptic signal is an all-or-none spike, the probabilistic manner of neurotransmitter release causes variation in the amplitudes of postsynaptic potentials. I have measured the reliability of the operation of synapses that convey small graded potentials between pairs of identified large, second-order neurons in the locust ocellar system. IPSPs are mediated by small rebound spikes, which are graded in amplitude, in the presynaptic neuron. A transfer curve plotting amplitudes of spikes against amplitudes of IPSPs has a characteristic S shape with a linear central portion where IPSP amplitude is between −0.2 and −0.6 as large as spike amplitude but shows appreciable scatter. Approximately half of the scatter is attributable to background noise, most of which originates in photoreceptors and persists in darkness. The remaining noise is intrinsic to the synapse itself and is usually 0.3–0.7 mV in amplitude. It limits the resolution with which two spike amplitudes can be distinguished from one another to ∼2 mV and, because the linear part of the transfer curve occupies ∼10 mV in spike amplitudes, limits the number of discrete signal levels that can be conveyed across the synapse to approximately five. The amplitude of the noise is constant throughout the synaptic operating range, which means it is unlikely that presynaptic membrane potential controls transmitter release by setting a single probability level for quantal release.
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龙虾口胃神经节分级突触传递的时间动态。
DOI：
10.1523/jneurosci.17-14-05610.1997
发表时间：
1997
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Manor,Y;Nadim,F;Abbott,LF;Marder,E
通讯作者：
Marder,E
蟑螂中多余的感觉神经元和正常的感觉神经元之间的竞争性相互作用是通过量子含量的变化而不是量子大小的变化来介导的。
影响因子：
2.5
作者：
Sosa,MA;Blagburn,JM
通讯作者：
Blagburn,JM
螃蟹的非冲动拉伸感受器复合体：强直感觉运动突触的去极化-释放耦合研究。
DOI：
10.1098/rstb.1980.0092
发表时间：
1980
期刊：
Proceedings of the Clinical Dialysis and Transplant Forum
影响因子：
--
作者：
Blight,AR;Llinás,R
通讯作者：
Llinás,R
板球尾部系统中四个已识别的初级感觉中间神经元动态编码的信息论分析。
DOI：
10.1152/jn.1996.75.4.1345
发表时间：
1996
期刊：
Journal of neurophysiology.
影响因子：
--
作者：
Theunissen,F;Roddey,JC;Stufflebeam,S;Clague,H;Miller,JP
通讯作者：
Miller,JP