preprints.org > biology and life sciences > neuroscience and neurology > doi: 10.20944/preprints202308.1296.v1

Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Version 1 : Received: 17 August 2023 / Approved: 17 August 2023 / Online: 18 August 2023 (10:59:31 CEST)

Cerebrospinal fluid contacting neurons (CSF-cNs) are a specific type of neurons located around the ventricles in the brain and the central canal in the spinal cord and have been demonstrated to be intrinsic sensory neurons in the central nervous system (CNS). One of the important channels responsible for the sensory function is polycystic kidney disease 2-like 1 (PKD2L1) channel. Most of the studies concerning the distribution and function of the PKD2L1-expressing CSF-cNs in the spinal cord have previously been performed in non-mammalian vertebrates. In the present study immunohistochemistry was performed to determine the distribution of PKD2L1-immunoreactive (IR) CSF-cNs in the spinal cords of 4 mammalian species: mouse, rat, cat, and macaque monkey. Here, we found that PKD2L1-expressing CSF-cNs were present at all levels of the spinal cord in these animal species. Although the distribution pattern was similar across these species, differences existed. Mice and rats presented a clear PKD2L1-IR cell body labeling, whereas in cats and macaques the PKD2L1-IR cell bodies were more weakly labeled. Ectopic PKD2L1-IR neurons away from the ependymal layer were observed in all the animal species although the abundance and the detailed locations varied. The apical dendritic protrusions towards the lumen of the central canal were clearly seen in all the animal species, but the sizes of protrusion bulbs were different among the species. PKD2L1-IR cell bodies/dendrites were co-expressed with doublecortin, MAP2 (microtubule-associated protein 2) and aromatic L-amino acid decarboxylase, but not with NeuN (neuronal nuclear protein), indicating their immature property and ability to synthesis monoamine transmitters. In addition, in-situ hybridization performed in rats revealed PKD2L1 mRNA expression in the cells around the central canal. Our results indicate that the intrinsic sensory neurons are conserved across non-mammalian and mammalian vertebrates, and that this may play an essential role in the regulation of motor and sensory functions as well as in the maintenance of homeostasis in the CNS.

mammalians; spinal cord; central canal; CSF; CSF-cNs; intrinsic sensory neurons; transient receptor potential channels

Biology and Life Sciences, Neuroscience and Neurology

* All users must log in before leaving a comment