Sassoè-Pognetto Marco
Department of Anatomy, Pharmacology and Forensic Medicine, and National Institute of Neuroscience, University of Torino, Torino, Italy.
Brain Res Rev. 2011 Jan 7;66(1-2):35-42. doi: 10.1016/j.brainresrev.2010.06.003. Epub 2010 Jun 19.
In 1875 Camillo Golgi published his classical description of the olfactory bulb, which contained the first images of neurons visualized with the "black reaction". This new staining method opened the way for structural investigations of the nervous tissue, that culminated in the extraordinary neuroanatomical work of Ramón y Cajal and the formulation of the neuron doctrine. Later developments in neurochemical techniques have revealed an astonishing diversity of neural circuits at the molecular level. This essay reflects on the physiological importance of the molecular heterogeneity of synaptic connections. Dendrodendritic circuits of the olfactory bulb will serve as a case for illustrating the relation between molecular composition and functional properties. Specifically, I will consider how the differential expression of GABA(A) receptor subtypes shapes dendrodendritic inhibition and influences olfactory bulb network activities. A concept emerging from recent investigations is that the molecular diversity of GABAergic systems supports neural circuit operations under an extensive range of behavior-dependent network states. Considering the great molecular diversity of synaptic connections, it is useful to reflect on the importance of high-resolution immunohistochemical analyses as a tool for investigating the structural and functional architecture of neural circuits.
1875年，卡米洛·高尔基发表了他对嗅球的经典描述，其中包含了用“黑色反应”可视化神经元的首批图像。这种新的染色方法为神经组织的结构研究开辟了道路，最终促成了拉蒙·伊·卡哈尔卓越的神经解剖学研究以及神经元学说的形成。神经化学技术的后续发展揭示了分子水平上神经回路惊人的多样性。本文探讨了突触连接分子异质性的生理重要性。嗅球的树突 - 树突回路将作为一个例子来说明分子组成与功能特性之间的关系。具体而言，我将探讨GABA(A)受体亚型的差异表达如何塑造树突 - 树突抑制并影响嗅球网络活动。最近研究中出现的一个概念是，GABA能系统的分子多样性在广泛的行为依赖网络状态下支持神经回路的运作。鉴于突触连接的巨大分子多样性，思考高分辨率免疫组织化学分析作为研究神经回路结构和功能架构工具的重要性是很有意义的。
