Locating TRPV1 Positive Sensory Fibers in Renal Anatomy to Suggest the Importance of Mechanosensation in Hemodynamic Regulation
High blood pressure is the primary factor for cardiovascular disease and is also regulated by the sympathetic nervous system. The kidneys are innervated by sensory (afferent) nerves, which are thought to modulate sympathetic activity via the central nervous system. Previous studies in the Osborn lab have suggested that the sensory fibers are in close relationship with glomeruli in the kidney, the filtration unit of the nephrons. Understanding their expression of different ion channels was used as an approach in researching their function in sensing glomerular changes. The expression of TRPV1, a mechanosensitive ion channel, in renal sensory fibers was explored in these studies. Immunofluorescently stained kidney slices from transgenic mice expressing tdTomato under the TRPV1 promoter were imaged to understand the interactions between TRPV1-positive fibers and glomeruli. The large-volume images provided evidence of the presence of TRPV1 in the kidneys. The presence of TRPV1-positive fibers near and surrounding glomeruli at all depths of the renal cortex was identified, suggesting a potential relationship to the role of mechanosensation in kidney-based hemodynamic regulation.