The morphological substrate for Renal Denervation: Nerve distribution patterns and parasympathetic nerves. A...

Area of Science:

• Anatomy
• Autonomic Nervous System
• Nephrology

Background:

• Renal denervation is a potential hypertension treatment, but renal artery nerve distribution is not fully understood.
• Previous studies identified sympathetic and sensory nerves, but not parasympathetic fibers.

Purpose of the Study:

• To map human renal nerve distribution patterns.
• To quantify the sympathetic, parasympathetic, and afferent contributions to the autonomic nervous system in the renal artery.

Main Methods:

• Human cadaver renal arteries were sectioned longitudinally and stained for nerve markers.
• Computerized image analysis quantified nerve fibers relative to their distance from the lumen.

Main Results:

• Sympathetic nerves constituted 73.5%, parasympathetic 17.9%, and afferent 8.7% of nerve area.
• Nerves were closer to the lumen in distal segments; optimal ablation depth varied by segment.
• Larger nerve bundles innervating the kidney were located 1-3.5mm from the lumen.

Conclusions:

• Sympathetic, parasympathetic, and afferent nerves are present around the renal artery.
• Further research into the parasympathetic nervous system's role in renal function is warranted.
• Findings could refine renal denervation by targeting distal segments.