Molecular Mechanisms of the Sense of Touch: An Overview of Mechanical Transduction and Transmission in Merkel Discs of Whisker Hair Follicles and Some Clinical Perspectives

  • Jianguo G. GuEmail author
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1099)


The Merkel disc is a main type of tactile end organs for sensing gentle touch and is essential for sophisticated sensory tasks including social interaction, environmental exploration, and tactile discrimination. Recent studies have shown that Merkel cells are primary sites of mechanotransduction using Piezo2 channels as a molecular transducer in Merkel discs. Furthermore, tactile stimuli trigger serotonin release from Merkel cells to excite their associated whisker Aβ-afferent endings and transmit tactile signals. The tactile transduction and transmission at Merkel discs may have important clinical implications in sensory dysfunctions such as the loss of tactile sensitivity and tactile allodynia seen in patients who have diabetes and inflammatory diseases and undergo chemotherapy.


Merkel disc Tactile sensation Whisker hair follicles Mechanical transduction and transmission Sensory dysfunction 


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of Anesthesiology and Perioperative Medicine, School of MedicineUniversity of Alabama at BirminghamBirminghamUSA

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