Mapping brain regions processing colorectal nociception

Extrinsic nerves innervating the colon are important to the regulation and integration of autonomic (i.e. motility) and sensory (i.e. pain) functions. This study aimed to identify the brain circuits into which extrinsic nerves from the distal colon convey nociceptive information in the mouse. Anterograde trans-neuronal tracing with herpes simplex virus 1 expressing EGFP (HSV-H129-EGFP) was used from the colorectum to map the neuronal expression of EGFP in the CNS in a time dependent manner (ANS 2019 poster attached). To identify brain regions engaged by colonic nociceptive stimuli the number of neurons activated by noxious in vivo colorectal distension was compared to that evoked by no distension (2021 Global Connectome poster attached). Male and female mice allowed for sex comparisons in how colorectal pain processing may be differentially processed within central pathways.支配结肠的外源性神经（extrinsic nerves）对于自主神经（即运动功能）与感觉（即疼痛）功能的调控与整合至关重要。本研究旨在明确小鼠体内，远端结肠的外源性神经将伤害性信息（nociceptive information）传递至的脑环路。本研究采用表达增强型绿色荧光蛋白（EGFP）的单纯疱疹病毒1型（HSV-H129-EGFP）开展顺行跨神经元追踪（anterograde trans-neuronal tracing），从结直肠部位入手，以时间依赖性方式绘制中枢神经系统（Central Nervous System，CNS）内EGFP的神经元表达图谱（附件包含2019年ANS会议海报）。为明确结肠伤害性刺激所激活的脑区，本研究将体内施加伤害性结直肠扩张刺激时激活的神经元数量，与未施加扩张刺激的对照组进行了对比（附件包含2021年全球连接组会议海报）。本研究纳入雄性与雌性小鼠，以比较结直肠疼痛加工在中枢通路中可能存在的性别差异性调控模式。