Peripheral sensitization, decrease in pain threshold in sensory neurons, can cause chronic pain. Little is known about how peripheral sensitization led to chronic pain. Here, we aimed to develop a method for evaluating peripheral sensitization in cultured sensory neurons with electrical recording. Sensory neurons from rat dorsal root ganglion were cultured on high-density microelectrode arrays (HD-MEA), and their activity was evoked by capsaicin stimulation with or without substance P. Fluorescent imaging-based electrode selection effectively selected five times as many capsaicin-sensitive sensory neurons as the existing method. Peripheral sensitization by substance P was detected from 31.9% of selected sensory neurons, and majority of these neurons co-expressed capsaicin and substance P receptors. These results indicate that our method is suitable for evaluating peripheral sensitization by substance P in cultured sensory neurons.

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开发培养感觉神经元外周敏化的评估方法

外周敏化，感觉神经元痛阈降低，可导致慢性疼痛。人们对于外周敏化如何导致慢性疼痛知之甚少。在这里，我们的目标是开发一种通过电记录评估培养的感觉神经元的外周敏化的方法。在高密度微电极阵列 (HD-MEA) 上培养大鼠背根神经节的感觉神经元，并通过有或没有 P 物质的辣椒素刺激来诱发其活动。基于荧光成像的电极选择有效地选择了五倍的辣椒素敏感细胞感觉神经元作为现有方法。从 31.9% 的选定感觉神经元中检测到 P 物质的外周敏化，并且这些神经元中的大多数共表达辣椒素和 P 物质受体。