Merkel cells are rare epidermal cells whose function in the skin is still debated. These cells localize to highly touch-sensitive areas of vertebrate epithelia, including palatine ridges, touch domes and finger tips. In most cases, Merkel cells complex with somatosensory afferents to form slowly adapting touch receptors; it is unclear, however, whether mechanosensory transduction occurs in the Merkel cell, the somatosensory afferent or both. Classic anatomical results suggests that Merkel cells are sensory cells that transduce mechanical stimuli and then communicate with sensory afferents via neurotransmission. This model is supported by recent molecular, immunohistochemical and physiological studies of Merkel cells in vitro and in intact tissues. For example, Merkel cells express essential components of presynaptic machinery, including molecules required for release of the excitatory neurotransmitter glutamate. Moreover, Merkel cells in vitro and in vivo are activated by mechanical stimuli, including hypotonic-induced cell swelling. Although these findings support the hypothesis that Merkel cells are sensory receptor cells, a definitive demonstration that Merkel cells are necessary and sufficient to transduce touch awaits future studies.

中文翻译：

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体感中的默克尔细胞。

默克尔细胞是罕见的表皮细胞，其在皮肤中的功能仍存在争议。这些细胞定位于脊椎动物上皮的高度触摸敏感区域，包括腭脊、触摸圆顶和指尖。在大多数情况下，默克尔细胞与体感传入复合，形成缓慢适应的触觉感受器。然而，尚不清楚机械感觉转导是否发生在默克尔细胞、体感传入神经或两者中。经典的解剖结果表明，默克尔细胞是感觉细胞，可以传导机械刺激，然后通过神经传递与感觉传入进行交流。该模型得到了最近对默克尔细胞体外和完整组织的分子、免疫组织化学和生理学研究的支持。例如，默克尔细胞表达突触前机制的重要组成部分，包括释放兴奋性神经递质谷氨酸所需的分子。此外，默克尔细胞在体外和体内都会被机械刺激激活，包括低渗引起的细胞肿胀。尽管这些发现支持默克尔细胞是感觉受体细胞的假设，但默克尔细胞对于传导触觉是必要且充分的明确证明还有待未来的研究。