The maintained discharge of rat retinal ganglion cells
The maintained discharge of rat retinal ganglion cells
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DOI：
10.1017/s095252380808067x
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发表时间：
2008-07-01
影响因子：
1.9
通讯作者：
Passaglia, Christopher L.
中科院分区：
文献类型：
--
作者：
Freeman, Daniel K.;Heine, Walter F.;Passaglia, Christopher L.
在均匀电场作用下，记录了大鼠视网膜神经节细胞纤维的动作电位，并表征了维持的放电模式。在氯胺酮-赛拉津麻醉下记录到的棘波序列通常是静止的，而在乌拉坦麻醉下记录到的棘波序列通常表现出缓慢的、无驱动的、准周期的放电率波动。根据这些非平稳性，报道了主要在氯胺酮-二甲肼作用下收集的数据的棘波间隔分布和功率谱密度。大多数细胞具有多峰间隔分布，第一个峰在25.0-38.5ms范围内，随后的峰出现在第一个峰的整数倍处。单峰分布的细胞用Gamma分布函数拟合得很好。间隔和棘波计数统计数据显示，开细胞的放电速度往往比非开细胞的快，而且频率较高的细胞的放电方式更规则。变异系数覆盖所有单元格的宽值范围(0.43-0.97)。On细胞和Off细胞在相邻的棘波间期之间表现出连续的相关关系，而On细胞也表现出二级相关关系。具有多峰间隔分布的细胞功率谱在28.9~41.4赫兹范围内出现一个较强的高频峰值。在两种麻醉条件下都存在振荡，并以略低的频率在黑暗中持续，这意味着振荡是独立于任何光刺激而产生的，但可以被光水平调制。在相同类型的细胞和同一只眼睛中，振荡频率略有不同，这表明视网膜内存在多种振荡生成机制。具有高频振荡的细胞可以很好地用All积分-火模型描述，输入由高斯噪声和正弦组成，其中相位随机抖动以考虑振荡中存在的带宽。
Action potentials were recorded from rat retinal ganglion cell fibers in the presence of a uniform field, and the maintained discharge pattern was characterized. Spike trains recorded under ketamine-xylazine anesthesia were generally stationary, while those recorded under urethane anesthesia often showed slow, undriven, quasiperiodic fluctuations in firing rate. In light of these nonstationarities, interspike interval distributions and power spectral densities are reported for data collected primarily under ketamine-xylazine. The majority of cells had multimodal interval distributions, with the first peak in the range of 25.0-38.5 ms and the subsequent peaks Occurring at integer multiples of the first peak. Cells with unimodal distributions were fit well by a gamma distribution function. Interval and spike count statistics showed that ON cells tended to fire faster than OFF cells and that cells with higher rates fired in a more regular manner. with the coefficient of variation covering a wide range of values across all cells (0.43-0.97). Both ON and OFF cells show serial correlations between adjacent interspike intervals, while ON cells also showed second-order correlations. Cells with multimodal interval distribution showed a strong peak at high frequencies in the power spectra in the range of 28.9-41.4 Hz. Oscillations were present under both anesthetic conditions and persisted in the dark at a slightly lower frequency, implying that the oscillations are generated independent of any light stimulus but can be modulated by light level. The oscillation frequency varied slightly between cells of the same type and in the same eye, suggesting that multiple oscillatory generating mechanisms exist within the retina. Cells with high-frequency oscillations were described well by ail integrate-and-fire model with the input consisting of Gaussian noise plus a sinusoid where the phase, was jittered randomly to account for the bandwidth present in the oscillations.