Macdonald Christopher L, Silva Gabriel A
Department of Bioengineering, University of California San Diego, La Jolla, CA, USA.
Front Neuroeng. 2013 Jul 10;6:4. doi: 10.3389/fneng.2013.00004. eCollection 2013.
We constructed a model of calcium signaling in astrocyte neural glial cells that incorporates a positive feedback nucleation mechanism, whereby small microdomain increases in local calcium can stochastically produce global cellular and intercellular network scale dynamics. The model is able to simultaneously capture dynamic spatial and temporal heterogeneities associated with intracellular calcium transients in individual cells and intercellular calcium waves (ICW) in spatially realistic networks of astrocytes, i.e., networks where the positions of cells were taken from real in vitro experimental data of spontaneously forming sparse networks, as opposed to artificially constructed grid networks or other non-realistic geometries. This is the first work we are aware of where an intracellular model of calcium signaling that reproduces intracellular dynamics inherently accounts for intercellular network dynamics. These results suggest that a nucleation type mechanism should be further investigated experimentally in order to test its contribution to calcium signaling in astrocytes and in other cells more broadly. It may also be of interest in engineered neuromimetic network systems that attempt to emulate biological signaling and information processing properties in synthetic hardwired neuromorphometric circuits or coded algorithms.
我们构建了一个星形胶质神经胶质细胞中的钙信号模型,该模型纳入了一种正反馈成核机制,即局部钙的微小微区增加能够随机产生全局细胞及细胞间网络尺度的动态变化。该模型能够同时捕捉与单个细胞内钙瞬变以及星形胶质细胞空间真实网络中的细胞间钙波(ICW)相关的动态空间和时间异质性,也就是说,在这些网络中,细胞位置取自自发形成的稀疏网络的真实体外实验数据,而非人工构建的网格网络或其他非真实几何结构。这是我们所知的第一项工作,其中一个再现细胞内动态的钙信号细胞内模型固有地解释了细胞间网络动态。这些结果表明,应进一步通过实验研究成核类型机制,以测试其对星形胶质细胞及更广泛其他细胞中钙信号的贡献。它在试图在合成硬连线神经形态测量电路或编码算法中模拟生物信号和信息处理特性的工程神经模拟网络系统中可能也会受到关注。