Novel Projections to the Cerebrospinal Fluid-Contacting Nucleus From the Subcortex and Limbic System in Rat

• Main Authors: Si-Yuan Song (Author), Xiao-Meng Zhai (Author), Jia-Hao Dai (Author), Lei-Lei Lu (Author), Cheng-Jing Shan (Author), Jia Hong (Author), Jun-Li Cao (Author), Li-Cai Zhang (Author)
• Format: Book
• Published: Frontiers Media S.A., 2020-08-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Objective: To identify the novel projections received by the cerebrospinal fluid (CSF)-contacting nucleus from the subcortex and limbic system to understand the biological functions of the nucleus.Methods: The cholera toxin subunit B (CB), a retrograde tracer, was injected into the CSF-contacting nucleus in Sprague-Dawley rats. After 7-10 days, the surviving rats were perfused, and the whole brain and spinal cord were sliced for CB immunofluorescence detection. The CB-positive neurons in the subcortex and limbic system were observed under a fluorescence microscope, followed by 3D reconstructed with the imaris software.Results: CB-positive neurons were found in the basal forebrain, septum, periventricular organs, preoptic area, and amygdaloid structures. Five functional areas including 46 sub-regions sent projections to the CSF-contacting nucleus. However, the projections had different densities, ranging from sparse to moderate, to dense.Conclusions: According to the projections from the subcortex and limbic system, we hypothesize that the CSF-contacting nucleus participates in emotion, cognition, homeostasis regulation, visceral activity, pain, and addiction. In this study, we illustrate the novel projections from the subcortex and limbic system to the CSF-contacting nucleus, which underlies the diverse and complicated circuits of the nucleus in body regulations.

Item Description

1662-5129
10.3389/fnana.2020.00057