The pilo-Ruffini complex: a non-sinus hair and associated slowly-adapting mechanoreceptor in primate facial skin.

A spray-type of nerve ending identified as a Ruffini corpuscle closely associated with a non-sinus hair has been defined in terms of its histologic, ultrastructural and physiologic parameters. The hair and its associated mechanoreceptor, termed a pilo-Ruffini complex, responds as a slowly adapting (SA) mechanoreceptor, whereas most non-sinus hair-associated mechanoreceptors are rapidly adapting. Morphologically, the terminal nerve fibers branch repeatedly within a unique connective tissue matrix, and the neurite and associated connective tissue matrix forms a collar around the hair follicle. This receptor, on the basis of its organization, is interpreted as corresponding to the corpuscle or end organ of Ruffini.