Distribution of P2X3-Immunoreactive Fibers in Hairy and Glabrous Skin of the Rat
April 2009
in “
Journal of comparative neurology
”
TLDR P2X<sub>3</sub>-IR fibers are widespread in rat skin and likely help detect pain.
The study investigated the pattern of P2X<sub>3</sub>-immunoreactive (IR) fiber innervation in the hairy and glabrous skin of male Sprague-Dawley rats using light microscopic immunocytochemistry. Results showed extensive P2X<sub>3</sub>-IR fibers throughout the upper and lower dermis, with thick bundles running parallel to the dermal-epidermal junction and projecting thin collateral axons into the epidermis, creating a dense network. The distribution of P2X<sub>3</sub>-IR fibers was more extensive than CGRP-IR fibers and also innervated hair follicles but were rarely near glands and blood vessels. These findings suggested a primary role for P2X<sub>3</sub>-IR fibers in detecting noxious stimuli in cutaneous tissue and provided an anatomical basis for future studies on the distinct functional role of nonpeptidergic nociceptors in nociceptive signal transmission.
