Bouskila Y, Dudek F E
Department of Anatomy and Neurobiology, Colorado State University, Fort Collins 80523, USA.
Brain Res. 1995 Jan 30;670(2):333-6. doi: 10.1016/0006-8993(94)01356-m.
The firing rate of a population of SCN neurons in vivo exhibits stable circadian oscillations, but the period length of individual neurons is not known and may be different or similar to the population rhythm. To address this question we used published data from Bos and Mirmiran [Brain Res., 511 (1990) 158-162] that reported different period lengths and amplitudes for individual neurons recorded in explant cultures of the SCN. We reconstructed the individual rhythms for several cycles, calculated the population rhythm, and then tested its stability. The period and amplitude of the rhythm of groups of neurons with different period lengths were unstable. Furthermore, the stability of the rhythm was reduced as the number of sampled neurons increased. These results suggest that the stable circadian rhythm reported for neuron populations in the intact SCN emerges from the identical period length of individual neurons. The possible intercellular interactions in the SCN that may underlie the stable circadian rhythm are discussed.
在体内，一群视交叉上核（SCN）神经元的放电频率呈现出稳定的昼夜节律振荡，但单个神经元的周期长度尚不清楚，可能与群体节律不同或相似。为了解决这个问题，我们使用了博斯和米尔米兰[《脑研究》，511（1990）158 - 162]发表的数据，这些数据报道了在SCN外植体培养物中记录的单个神经元的不同周期长度和振幅。我们重建了几个周期的个体节律，计算了群体节律，然后测试了其稳定性。具有不同周期长度的神经元群体节律的周期和振幅不稳定。此外，随着采样神经元数量的增加，节律的稳定性降低。这些结果表明，完整SCN中报道的神经元群体的稳定昼夜节律源自单个神经元相同的周期长度。文中还讨论了SCN中可能构成稳定昼夜节律基础的细胞间相互作用。
