Lamellar cells in Pacinian and Meissner corpuscles are touch sensors

Area of Science:

• Neuroscience
• Cell Biology
• Sensory Physiology

Background:

• The skin's tactile organs, like Meissner and Pacinian corpuscles, contain sensory neurons and surrounding lamellar cells.
• The precise function of lamellar cells in touch detection has remained largely unknown.
• Neuronal afferents were traditionally considered the sole mechanical sensors in these corpuscles.

Purpose of the Study:

• To investigate the functional role of lamellar cells in tactile sensation.
• To determine if lamellar cells possess mechanosensory capabilities.
• To explore the molecular mechanisms underlying lamellar cell mechanotransduction.

Main Methods:

• Developed an electrophysiological preparation using duck bill skin, a specialized tactile organ.
• Recorded from lamellar cells within Meissner and Pacinian corpuscles.
• Utilized techniques to identify and activate mechanically gated ion channels and voltage-gated calcium channels.

Main Results:

• Demonstrated that lamellar cells contain mechanically gated ion channels, responding to tactile stimuli.
• Showed that lamellar cells in Meissner corpuscles generate action potentials.
• Identified R-type voltage-gated calcium channels as crucial for these action potentials in non-neuronal cells.

Conclusions:

• Lamellar cells actively detect touch, challenging the exclusive role of neurons in mechanoreception.
• This study provides the first evidence of action potentials in non-neuronal cells mediated by R-type calcium channels.
• Meissner and Pacinian corpuscles likely employ both neuronal and non-neuronal mechanoreception for comprehensive touch detection.