Neurotransmitters and synaptic components in the Merkel cell-neurite complex, a gentle-touch receptor

• Published in: Annals of the New York Academy of Sciences Vol. 1279; no. 1; pp. 13 - 21
• Main Authors: Maksimovic, Srdjan, Baba, Yoshichika, Lumpkin, Ellen A.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.03.2013; Wiley Subscription Services, Inc
• Subjects: Animals; Cell Communication - physiology; Humans; mechanotransduction; Merkel cell; Merkel Cells - metabolism; Merkel Cells - physiology; Models, Biological; Neurites - metabolism; Neurites - physiology; neuromodulator; Neurons; neurotransmitter; Neurotransmitter Agents - metabolism; Neurotransmitter Agents - physiology; Neurotransmitters; Sensory Receptor Cells - metabolism; Sensory Receptor Cells - physiology; somatosensory; Synapses - metabolism; Synapses - physiology; touch; Touch - physiology
• ISSN: 0077-8923; 1749-6632
• DOI: 10.1111/nyas.12057

Merkel cells are an enigmatic group of rare cells found in the skin of vertebrates. Most make contacts with somatosensory afferents to form Merkel cell–neurite complexes, which are gentle‐touch receptors that initiate slowly adapting type I responses. The function of Merkel cells within the complex remains debated despite decades of research. Numerous anatomical studies demonstrate that Merkel cells form synaptic‐like contacts with sensory afferent terminals. Moreover, recent molecular analysis reveals that Merkel cells express dozens of presynaptic molecules that are essential for synaptic vesicle release in neurons. Merkel cells also produce a host of neuroactive substances that can act as fast excitatory neurotransmitters or neuromodulators. Here, we review the major neurotransmitters found in Merkel cells and discuss these findings in relation to the potential function of Merkel cells in touch reception.