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bioRxiv · 10.1101/633115

A labeled-line for cold from the periphery to the parabrachial nucleus

Abstract

Spinal projection neurons are a major pathway through which somatic stimuli are conveyed to the brain. However, the manner in which this information is coded is poorly understood. Here, we report the identification of a modality-selective spinoparabrachial (SPB) neuron subtype with unique properties. Specifically, we find that cold-selective SPB neurons are differentiated by selective afferent input, reduced neuropeptide sensitivity, distinct physiological properties, small soma size, and low basal drive. In addition, optogenetic experiments reveal that cold-selective SPB neurons are distinctive with respect to their connectivity, with little to no input from either Pdyn or Nos1 inhibitory interneurons. Together, these data define a neural substrate supporting a labeled-line for cold from the periphery to the brain.

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BibTeXRIS

Ross, S. E., Hachisuka, J., Koerber, H. R.. 2019-05-09. A labeled-line for cold from the periphery to the parabrachial nucleus. https://doi.org/10.1101/633115

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