投射至中缝背核的脑干感觉中继核团的鉴定  

Identification of sensory relay nuclei in brainstem that projecting to the dorsal raphe nucleus

作　　者：张偲 罗芬兰[1] 任栓成 胡志安[1] ZHANG Cai;LUO Fenlan;REN Shuancheng;HU Zhi’an(Department of Physiology,Collaborative Innovation Center for Brain Science,College of Basic Medical Sciences,Army Medical University(Third Military Medical University),Chongqing,400038;Department of Emergency,No.953 Hospital PLA Army,Shigatse,Tibet Autonomous Region,857000,China)

机构地区：[1]陆军军医大学(第三军医大学)基础医学院生理学教研室,脑与智能研究院,重庆400038 [2]陆军第953医院急诊医学科,西藏日喀则857000

出　　处：《第三军医大学学报》2021年第9期771-778,共8页Journal of Third Military Medical University

基　　金：国家自然科学基金创新研究群体项目(31921003)。

摘　　要：目的利用神经环路示踪技术,观察投射至中缝背核(dorsal raphe nucleus,DRN)的脑干感觉中继核团的分布与联系模式,探究感觉信息调控觉醒/睡眠的形态学基础。方法采用逆行示踪技术,于正常成年C57BL/6小鼠(n=3)DRN注射逆行荧光微粒RetroBeads,观察脑干感觉中继核团RetroBeads表达情况。进一步在小鼠(n=3)多种感觉中继核团臂旁核(parabrachial nucleus,PBN)注射AAV-CaMKIIα-EGFP和RetroBeads,分别观察其纤维末梢在DRN的分布情况及其接受的脑干感觉输入。结果通过在DRN注射RetroBeads,发现投射至DRN的脑干感觉中继核团包括:上橄榄核、孤束核头侧、孤束核尾侧、前庭内侧核旁细胞部和前庭内侧核巨细胞部,分别占DRN脑干总输入的3.11%、2.95%、10.40%、10.45%和1.75%。此外,脑干内同时中继多种感觉的PBN有大量RetroBeads标记的神经元,占DRN脑干总输入的71.33%。AAV-CaMKIIα-EGFP介导的顺行示踪发现PBN神经元向DRN发出致密的纤维投射。PBN注射RetroBeads观察其接受的脑干感觉输入发现,PBN接受中继头面部痛温觉、触压觉的三叉神经感觉主核和脊束核的神经输入,分别占PBN脑干总输入的6.14%和49.86%。孤束核头侧、孤束核尾侧与前庭内侧核旁细胞部也投射至PBN,其输入分别占PBN脑干总输入的11.67%、20.53%与8.94%。此外,感觉中继核团下橄榄核发现少量标记的神经元,占PBN脑干总输入的2.14%。结论DRN接受来自脑干感觉中继核团孤束核、上橄榄核、前庭核群的直接输入,同时也通过PBN间接接受三叉神经感觉主核、三叉神经脊束核和下橄榄核的输入。Objective To explore the distribution and contact pattern of sensory relay nuclei in the brainstem that projecting to the dorsal raphe nucleus(DRN)by using neural circuit tracing technique,so as to investigate the morphological basis of sensory information regulating wakefulness/sleep.Methods Retrograde transporting tracing fluorescent particles RetroBeads were injected into the DRN of adult male C57BL/6 mice(n=3),and the expression of RetroBeads was observed in the sensory relay nuclei of the brainstem.Furthermore,AAV-CaMKIIα-EGFP and RetroBeads were injected into the parabrachial nucleus(PBN)of another 3 mice to observe the distribution of the fiber terminals in DRN and the sensory inputs from the brainstem.Results By the injection of RetroBeads into the DRN,we identified the sensory relay nuclei projecting to the DRN.These nuclei included the superior olivary nucleus,rostral solitary tract nucleus,caudal solitary tract nucleus,parvicellular part of medial vestibular nucleus and magnocellular part of medial vestibular nucleus,accounting for 3.11%,2.95%,10.40%,10.45% and 1.75% of the total brainstem inputs of the DRN,respectively.In addition,there were a large number of RetroBeads labeled neurons in the PBN,accounting for 71.33%of the total input of DRN.Meanwhile,AAV-CaMKIIα-EGFP mediated anterograde tracing showed that the PBN neurons sent dense fiber projections to the DRN.PBN received the inputs form the trigeminal sensory nucleus and spinal tract nucleus,which relay pain,temperature and touch sensation of the head and face.They accounted for 6.14% and 49.86% of the total brainstem input of PBN.The rostral solitary tract nucleus,caudal solitary tract nucleus and parvicellular part of medial vestibular nucleus also projected to the PBN,accounting for 11.67%,20.53% and 8.94% of the total brainstem input of PBN,respectively.In addition,a few labeled neurons were found in the inferior olivary nucleus,accounting for 2.14% of the total brainstem input of PBN.Conclusion The DRN receives the direct inputs from the

关 键 词：中缝背核 臂旁核 感觉中继核团 神经束路追踪 

分 类 号：R337.3[医药卫生—人体生理学] R338.22[医药卫生—基础医学]