Large-Scale Analysis of the Diversity and Complexity of the Adult Spinal Cord Neurotransmitter Typology

• Published in: iScience 2019-09, Vol.19, p.1189-1201
• Main Authors: Pedroni, Andrea, Ampatzis, Konstantinos
• Format: Article
• Language: English
• Subjects: Biological Sciences; Neuroanatomy; Neuroscience; Systems Neuroscience
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2019.09.010

The development of nervous system atlases is a fundamental pursuit in neuroscience, since they constitute a fundamental tool to improve our understanding of the nervous system and behavior. As such, neurotransmitter maps are valuable resources to decipher the nervous system organization and functionality. We present here the first comprehensive quantitative map of neurons found in the adult zebrafish spinal cord. Our study overlays detailed information regarding the anatomical positions, sizes, neurotransmitter phenotypes, and the projection patterns of the spinal neurons. We also show that neurotransmitter co-expression is much more extensive than previously assumed, suggesting that spinal networks are more complex than first recognized. As a first direct application, we investigated the neurotransmitter diversity in the putative glutamatergic spinal V2a-interneuron assembly. These studies shed new light on the diverse and complex functions of this important interneuron class in the neuronal interplay governing the precise operation of the central pattern generators. [Display omitted] •The structural organization of the adult zebrafish spinal cord is highly diverse•Equal number of ascending and descending neurons are excitatory or inhibitory•Several (∼15%) spinal neurons express multiple neurotransmitter phenotypes•Part of the glutamatergic V2a-INs co-express GABA, glycine, or acetylcholine Biological Sciences; Neuroscience; Systems Neuroscience; Neuroanatomy