Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, USA.
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, USA.
Biochem Biophys Res Commun. 2018 Nov 30;506(3):709-715. doi: 10.1016/j.bbrc.2018.10.120. Epub 2018 Oct 28.
Reactive oxygen species (ROS) modulate neuronal function, including plasticity and neurotransmitter biosynthesis and release. The cellular mechanisms that underlie redox modulation of neurotransmission are not fully resolved, but potential pathways include ROS-induced alterations in Ca signaling in nerve terminals. In this study, we show that cold-sensitive receptor TRPM8 is activated by pro-oxidant tert-butyl hydroperoxide (tBHP). Polymerase chain reaction, Western immunoblotting, and immunofluorescence indicated that TRPM8 channels are expressed in rat pheochromocytoma 12 (PC12) cells, a phenotypic model of sympathetic neurosecretion when differentiated with nerve growth factor. WS-12, a selective TRPM8 channel agonist, and tBHP increased intracellular Ca concentration in differentiated PC12 cells; an effect attenuated by AMTB, a selective TRPM8 channel blocker, and siRNA-mediated TRPM8 knockdown. Blockade of TRPM8 channels also reduced WS-12- and tBHP-evoked norepinephrine secretion from the cells. These data suggest that TRPM8 channels contribute to oxidant-induced neurotransmission in PC12 cells.
活性氧（ROS）调节神经元功能，包括可塑性和神经递质的生物合成和释放。ROS 调节神经递质传递的细胞机制尚未完全阐明，但潜在途径包括 ROS 诱导的神经末梢 Ca 信号改变。在这项研究中，我们表明，促氧化剂叔丁基过氧化物（tBHP）激活冷敏感受体 TRPM8。聚合酶链反应、Western 免疫印迹和免疫荧光表明，TRPM8 通道在大鼠嗜铬细胞瘤 12 （PC12）细胞中表达，当用神经生长因子分化时，PC12 细胞是交感神经分泌的表型模型。TRPM8 通道的选择性激动剂 WS-12 和 tBHP 增加了分化的 PC12 细胞内的 Ca 浓度；这种作用被选择性 TRPM8 通道阻滞剂 AMTB 和 siRNA 介导的 TRPM8 敲低所减弱。TRPM8 通道的阻断也减少了 WS-12 和 tBHP 诱发的细胞内去甲肾上腺素分泌。这些数据表明，TRPM8 通道有助于 PC12 细胞中氧化剂诱导的神经递质传递。
