Abstract
The slow-closing phase of the mastication cycle plays a major role in the mastication of foods. However, the neuronal mechanism underlying the slow-closing phase remains unknown. During the slow-closing phase, isometric contraction of jaw-closing muscles is developed through the recruitment of jaw-closing motoneurons (MNs). It is well established that motor units are recruited depending on the order of sizes or input resistances (IRs) of MNs, which is known as the size principle. TASK1/3 channels are recently found to be the molecular correlates of the IR, and also found to be expressed in the masseter MNs. The orderly recruitment of masseter MNs may be modified by the activity of TASK1/3 channels. In this chapter, we discuss the synaptic mechanisms underlying the orderly recruitment of masseter MNs that occurs during the slow-closing phase, together with the mechanism for the modulation of the orderly recruitment of motor units.
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Kang, Y., Toyoda, H., Saito, M., Sato, H. (2010). Recruitment of masseter motoneurons by spindle Ia inputs and its modulation by leak K+ channels. In: Sasano, T., Suzuki, O. (eds) Interface Oral Health Science 2009. Springer, Tokyo. https://doi.org/10.1007/978-4-431-99644-6_9
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DOI: https://doi.org/10.1007/978-4-431-99644-6_9
Publisher Name: Springer, Tokyo
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