About this Research Topic
During the 90s, a number of observations made in primary astrocytic cell cultures convinced scientists to reconsider the physiological role of astrocytes as solely structural and metabolic partners of neurons. Resulting literature have confirmed these hypotheses in brain slice preparations; but soon after a wave of excitement for the new findings on calcium waves and astrocytic release of neuroactive molecules, new technologies in the fields of molecular biology and microscopy have significantly challenged these previous works to a point where the aforementioned points remain an open question.
One reason why scientists are still struggling to elucidate the mechanisms by which glia play a role in neuronal connectivity relies on the fact that technological advancements in brain research are mainly driven by the need to understand neurons. Glial scientists often need to adapt existing approaches to their purpose, and engineer tools that are either not specific enough, or alter cellular mechanisms in such a way that the findings described might be considered as artifacts. On the contrary, the study of neurons progressed slowly and steady, in a balanced fashion between knowledge and state of the art technological tools. For instance, when Santiago Ramon y Cajal and Camillo Golgi became interested in neuroscience, they took advantage of the best tools available at that time (light microscopy, the "black reaction", and their artistic skills) to describe the morphology of brain cells, which was still poorly understood. Astrocytes were immediately recognized for their potential role as metabolic bridge between the circulatory system and the neurons; but because of their evident supporting role, no further effort was put in their characterization. The sudden fall of interest in these cells, compared to the “more interesting” neurons, among other reasons, can be explained with the fact that basic structural details about astrocytes, such as numbers of synapses in direct contact in a certain volume, presence/absence of intracellular organelles in specific domain of these cells, are still poorly investigated, and very limited literature is available on this topic.
Here, we propose a collection of works where scientists present detailed morphological analysis of glial cells, specifically using EM to address these questions, and possibly making their material available for the community.
Keywords: Glia, Astrocytes, Electron Microscopy, 3D reconstruction
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.