Background: Client-owned dogs commonly develop neuropathic and musculoskeletal pain, but little is known about the canine primary sensory neurons associated with pain pathways. Hypothesis/
Objectives: The objective of this study was to generate an atlas of canine primary sensory neurons from the dorsal root ganglia. We hypothesized that there would be a significant overlap in the cell types present in dog primary sensory neurons when compared to established human and rodent atlases, and the canine atlas would be a closer model to human atlases than rodents. Animals: Tissue from three client-owned dogs between the ages of one to nine.
Methods: A single-nuclei RNA sequencing study was performed by collecting the lumbosacral dorsal root ganglia from dogs that had no previous history of underlying orthopedic or neurologic disease. Nuclei isolation and single-nuclei RNA sequencing were then conducted on available dorsal root ganglia. An atlas was then generated for selected dorsal root ganglia and compared to available human and rodent atlases.
Results: Atlases were generated of selected dorsal root ganglia, and many cell types were identified, including neurons and non-neurons. Examples of neuronal markers include SNAP-25, RBFOX3, and SPARC. Generated atlases revealed similarities with human and rodent atlases. All known human neuronal subtypes were identified in the dog atlas. Conclusions and Clinical Importance: This study is the first to generate an atlas evaluating the canine primary sensory neurons and has the potential to improve the current understanding of pain in canine species and allow for the development of more targeted analgesics.
