The Pacinian corpuscle, also known as the lamellar corpuscle or the Vater-Pacini corpuscle, is one of the four basic types of mechanoreceptors found in mammalian skin. This type of mechanoreceptor is found in both hairy and hairless skin, viscera, joints, and bone periosteum, and is principally responsible for vibration sensitivity.
Pacinian corpuscles are fast-adaptable (phasic) receptors that sense changes in skin pressure and vibrations. As the corpuscle changes shape, channels for pressure- or stretch-activated ions or mechanosensitive signals open in the axon membrane or axolemma of the neurite inside the core of the corpuscle.
This deformation triggers the creation of the receptor potential within the corpuscles, which is also supported secondarily by the voltage-activated ion channels found in the corpuscle core. Finally, the receptor potential is modified to neural spikes or action potentials by the opening of sodium ion channels found at the axon’s first Ranveir’s Node.
These corpuscles are particularly sensitive to vibrations, which they can detect from a distance of several centimeters. Their optimal sensitivity is 250 Hz, which is the frequency range generated by textures with features smaller than 1 micrometer.
Pacinian corpuscles respond when the skin is rapidly indented but not when the pressure is steady, due to the layers of connective tissue that cover the nerve ending. It is thought that they respond to high-velocity changes in joint position. They have also been implicated in detecting the location of touch sensations on handheld tools.
References:
- Kandel, Eric R.; Schwartz, James H.; Jessell, Thomas M., eds. (2000). Principles of neural science. New York: McGraw-Hill, Health Professions Division. ISBN 0-8385-7701-6
- Purves, Dale; Augustine, George J.; Fitzpatrick, David; Katz, Lawrence C.; LaMantia, Anthony-Samuel; McNamara, James O.; Williams, S. Mark (2001). Cutaneous and Subcutaneous Somatic Sensory Receptors. Neuroscience. 2nd edition. Sinauer Associates.
- Skedung, Lisa, Martin Arvidsson, Jun Young Chung, Christopher M. Stafford, Birgitta Berglund, and Mark W. Rutland. 2013. Feeling Small: Exploring the Tactile Perception Limits. Sci. Rep. 3 (September 12). doi:10.1038/srep02617
Image: Drawing of the Pacinian corpuscle, with its system of capsules and central cavity. Credit: Henry Gray (1918) Anatomy of the Human Body, plate 935.