Primary sensory cells

Japanese: 一次感覚細胞 - いちじかんかくさいぼう

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[Sensory Reception Mechanism]
Receptors (receptor cells or sensory cells when referring to specific cells) are either neurons themselves, whose axons act as primary afferent fibers, or non-neuronal cells derived from epithelial cells, to which sensory neurons are synapsed. The former are called primary sensory cells (e.g., olfactory cells), and the latter are called secondary sensory cells (e.g., hair cells of the inner ear). Let us briefly explain the sensory reception mechanism using the stretch receptors of crustaceans as an example (Figure 1).

From [Sensory Cells]

…The receptor potential increases with the strength of the stimulus. There are two types of sensory cells: those that are themselves nerve cells and extend their axons toward the center (primary sensory cells), and those that do not have axons themselves and are controlled by separate sensory nerves (secondary sensory cells). In primary sensory cells, the receptor potential generates an action potential in the axon, which is transmitted to the afferent side. …

*Some of the terminology that refers to "primary sensory cells" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

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［感覚の受容機構］
　受容器(具体的に細胞を指すときは受容器細胞または感覚細胞という)はそれ自身がニューロンであって，軸索が第一次求心繊維として働くものと，それ自身は上皮細胞に由来する非ニューロン性細胞で，これに感覚ニューロンがシナプス結合しているものとある。前者を一次感覚細胞(例，嗅細胞)，後者を二次感覚細胞(例，内耳の有毛細胞)という。　感覚の受容機構を甲殻類の伸張受容器を例にして簡単に説明しよう(図1)。…