Allometric rules for mammalian cortical layer 5 neuron biophysics.
Allometric rules for mammalian cortical layer 5 neuron biophysics.
复制标题
DOI：
10.1038/s41586-021-04072-3
复制
发表时间：
2021-12
期刊：
影响因子：
64.8
通讯作者：
Harnett MT
中科院分区：
文献类型：
--
作者：
Beaulieu-Laroche L;Brown NJ;Hansen M;Toloza EHS;Sharma J;Williams ZM;Frosch MP;Cosgrove GR;Cash SS;Harnett MT
神经元的生物物理特性是大脑计算的基础。神经元大小是单个神经元输入输出特征的关键决定因素，并且在不同物种之间存在很大差异。然而，尚不清楚不同的物种是否适应神经元的特性来保存单个神经元处理信息的方式。在这里，我们描述了10种哺乳动物物种的第5层皮质锥体神经元，以确定控制神经元生物物理如何随细胞大小变化的异速关系。在10种中的9种中，我们观察到控制电压门控钾和HCN电导的守恒规律。神经元较大的物种，因此表面体积比降低，表现出更高的膜离子电导率。这种关系产生了单位脑容量的保守电导。这些依赖于大小的规则导致躯体和树突整合特性发生了巨大但可预测的变化。令人惊讶的是，人类神经元不遵循这些异速关系，表现出更低的电压门控钾和HCN电导。总之，我们在第5层神经元的研究结果确定了哺乳动物神经元生物物理学的新保守进化原则，以及人类皮层的意想不到的特征。
The biophysical properties of neurons are the foundation for computation in the brain. Neuronal size is a key determinant of single neuron input-output features and varies substantially across species. However, it is unknown if different species adapt neuronal properties to conserve how single neurons process information. Here, we characterize layer 5 cortical pyramidal neurons across 10 mammalian species to identify the allometric relationships that govern how neuronal biophysics change with cell size. In 9 of the 10 species, we observe conserved rules controlling voltage-gated potassium and HCN conductances. Species with larger neurons, and therefore decreased surface-to-volume ratio, exhibit higher membrane ionic conductances. This relationship produces a conserved conductance per unit brain volume. These size-dependent rules result in large but predictable changes in somatic and dendritic integrative properties. Surprisingly, human neurons do not follow these allometric relationships, exhibiting much lower voltage-gated potassium and HCN conductances. Together, our results in layer 5 neurons identify new conserved evolutionary principles for neuronal biophysics in mammals as well as unexpected features of the human cortex.