Department of Biomedical Chemistry major, Graduate School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo, Japan.
Department of Neurophysiology, Hyogo Medical University, Nishinomiya, Hyogo, Japan.
Sci Rep. 2023 Feb 20;13(1):2960. doi: 10.1038/s41598-023-29140-8.
Transient receptor potential ankyrin 1 (TRPA1) is a member of the TRP channel family and is expressed in peripheral and central nervous systems. In the periphery, TRPA1 senses cold and pain. However, the functions of TRPA1 in the CNS are unclear. Here, we examined the roles of TRPA1 on neural activity and synaptic transmission in layer II/III pyramidal neurons from mice anterior cingulate cortex (ACC) by whole-cell patch-clamp recordings. The activation of Cinnamaldehyde (CA), which is TRPA1 agonist produced inward currents and these were blocked by the TRPA1 antagonists. Furthermore, activating TRPA1 changed the properties of action potentials such as the firing rate, rise time and decay time. In contrast, stimulating TRPA1 did not alter the spontaneous synaptic transmission. Finally, we examined the functional role of TRPA1 on neurons in a hypoxic environment. We induced an acute hypoxia by substituting nitrogen (N) gas for oxygen (O) in the external solution. N produced biphasic effects that consisting of inward currents in the early phase and outward currents in the late phase. Importantly, blocking TRPA1 reduced inward currents, but not outward currents. In contrast, a K channel blocker completely inhibited outward currents. These results suggest that TRPA1 acts on postsynaptic neurons in the ACC as an acute O sensor.
瞬时受体电位锚蛋白 1（TRPA1）是 TRP 通道家族的一员，在周围和中枢神经系统中表达。在外周，TRPA1 感知冷和痛。然而，TRPA1 在中枢神经系统中的功能尚不清楚。在这里，我们通过全细胞膜片钳记录研究了 TRPA1 对小鼠扣带前皮质（ACC）II/III 层锥体神经元神经活动和突触传递的作用。肉桂醛（CA）的激活，即 TRPA1 激动剂，产生内向电流，这些电流被 TRPA1 拮抗剂阻断。此外，激活 TRPA1 改变了动作电位的特性，如放电率、上升时间和下降时间。相比之下，刺激 TRPA1 不会改变自发突触传递。最后，我们研究了 TRPA1 在缺氧环境下对神经元的功能作用。我们通过在外液中用氮气（N）代替氧气（O）来诱导急性缺氧。N 产生了双相作用，包括早期的内向电流和晚期的外向电流。重要的是，阻断 TRPA1 减少了内向电流，但没有减少外向电流。相反，一种 K 通道阻断剂完全抑制了外向电流。这些结果表明，TRPA1 在外侧扣带前皮质作为急性 O 传感器作用于突触后神经元。
