Lamellar cells in Pacinian and Meissner corpuscles are touch sensors

Abstract

The skin covering the human palm and other specialized tactile organs contains a high density of mechanosensory corpuscles tuned to detect transient pressure and vibration. These corpuscles comprise a sensory afferent neuron surrounded by lamellar cells. The neuronal afferent is thought to be the mechanical sensor within the corpuscle, whereas the function of lamellar cells is unknown. Here we show that lamellar cells within Meissner and Pacinian corpuscles detect tactile stimuli. We develop a preparation of bill skin from tactile-specialist ducks that permits electrophysiological recordings from lamellar cells and demonstrate that they contain mechanically-gated ion channels. We also show that lamellar cells from Meissner corpuscles generate mechanically-evoked action potentials using R-type voltage-gated calcium channels. These findings provide the first evidence for R-type channel-dependent action potentials in non-neuronal cells and demonstrate that lamellar cells are active detectors of touch. We propose that Meissner and Pacinian corpuscles use both neuronal and non-neuronal mechanoreception to detect mechanical signals.

The Human Cutaneous Sensory Corpuscles: An Update

“…For many years, they were exclusively related to the detection and discrimination of low-frequency vibration; however, they are also responsible for the detection of fine movements on the skin [ 29 ]. Furthermore, Meissner corpuscles have been proposed to function as nociceptors, as accessory axons express neuropeptides related to nociception [ 26 ], and evidence is being accumulated that not only axons but also lamellar cells are touch sensors [ 30 ].…”