The Functional Organization of Cutaneous Low-Threshold Mechanosensory Neurons

December 2011 in “ Cell ”

Lishi Li, Michael Rutlin, Victoria E. Abraira, Colleen Cassidy, Laura Kus, Shiaoching Gong, Michael P. Jankowski, Wenqin Luo, Nathaniel Heintz, H. Richard Koerber, C. Jeffery Woodbury, David D. Ginty

TLDR Different hair follicles in the skin are innervated by unique combinations of mechanosensory neurons, crucial for touch sensation.

The study investigated the organization of low-threshold mechanoreceptors (LTMRs) in the skin, specifically Aβ-, Aδ-, and C-LTMRs, through genetic labeling and visualization of their axonal endings. It was found that each type of hair follicle in trunk hairy skin (guard, awl/auchene, and zigzag hairs) is innervated by a unique combination of LTMRs, making each follicle a distinct mechanosensory end organ. Additionally, the central projections of these LTMRs form narrow columns in the dorsal horn of the spinal cord, suggesting that the integration of LTMR activities within these columns is crucial for processing touch sensations.