小鼠的下丘脑室旁核向前包钦格复合体直接投射参与调控呼吸  

Paraventricular hypothalamic nucleus projects directly to the preBtzinger complex and is involved in regulation of respiration in mice

作　　者：刘凌琳 张俊鸿 熊玮 LIU Linglin;ZHANG Junhong;XIONG Wei(Department of Geriatrics and Special Service Medicine,First Affiliated Hospital,Army Medical University(Third Military Medical University),Chongqing,400038,China)

机构地区：[1]陆军军医大学(第三军医大学)第一附属医院老年医学与特勤医学科,重庆400038

出　　处：《陆军军医大学学报》2024年第20期2265-2275,共11页Journal of Army Medical University

基　　金：国家重点研发计划(2018YFC2000301)。

摘　　要：目的 探究小鼠全脑呼吸相关核团的空间分布,以及下丘脑室旁核(paraventricular hypothalamic nucleus, PVN)与前包钦格复合体(preB9tzinger complex, preB9tC)之间的环路连接及投射关系。方法 运用从外周到中枢逆行示踪的研究策略,在小鼠的膈肌微量注射伪狂犬病毒(pseudorabies virus, PRV),逆行标记脊髓呼吸膈运动神经元的上游输入脑区。在PVN微量注射顺行不跨突触病毒(AAV2/9-EGFP),标记PVN下游脑区;并利用Cre/loxP基因表达策略,在PVN及preB9tC分别注射Dio-EGFP及Retro-Cre病毒,验证PVN-preB9tC环路及二者之间的投射关系。结果 PRV介导的逆行示踪结果显示:被PRV-EGFP标记的阳性神经元分布在PVN、preB9tC、孤束核(nucleus tractus solitarii, NTS)、蓝斑(locus coeruleus, LC)和中脑导水管周围灰质(periaqueductal gray, PAG)等多个脑区,除延髓区域外,PVN脑区的PRV-EGFP阳性神经元占比最高(P<0.000 1)。在PVN注射AAV2/9-EGFP,经病毒感染后在preB9tC脑区可见绿色神经纤维。在PVN和preB9tC分别注射Dio-EGFP及Retro-Cre病毒,经病毒感染后PVN脑区可见绿色神经元胞体。结论 PVN是脊髓呼吸膈运动神经元上游重要的输入核团,并有可能通过PVN-preB9tC环路的直接投射调控呼吸。ObjectiveTo probe the spatial distribution of respiratory-related nuclei throughout the whole brain,and to investigate the circuit and projection links between the paraventricular hypothalamic nucleus(PVN)and the preBtzinger complex(preBtC)in mice.MethodsUsing a retrograde tracing strategy from peripheral to central,pseudorabies viruses(PRV)were microinjected into the diaphragm of mice to retrogradely label the upstream inputs brain regions from spinal respiratory phrenic motor neurons.The anterograde non-transsynaptic tracing viruses(AAV2/9-EGFP)were microinjected into the PVN to label the downstream brain region of the PVN;And using the Cre/loxP gene expression strategy,Dio-EGFP and Retro-Cre viruses were injected in the PVN and preBtC,respectively,to validate the PVN-preBtC circuit and the projection relationship between the two.ResultsThe results of PRV-mediated retrograde tracing showed that PRV-EGFP-positive neurons were distributed in several brain regions such as PVN,preBtC,nucleus tractus solitarii(NTS),locus coeruleus(LC)and periaqueductal grey(PAG).Except for the medulla oblongata region,the PVN brain region had the highest percentage of PRV-EGFP-positive neurons(P<0.0001).After AAV2/9-EGFP viruses were injected in the PVN,green neurofibrils were observed in the preBtC brain region after viral infection;Dio-EGFP and Retro-Cre viruses were injected in the PVN and preBtC,respectively,and green neuronal cells were seen in the brain region of the PVN after viral infection.ConclusionPVN is an important upstream input nucleus of spinal respiratory phrenic motor neurons,and has the potential to regulate respiration through direct projections from PVN-preBtC circuit.

关 键 词：下丘脑室旁核 前包钦格复合体 呼吸运动神经网络 膈运动神经元 

分 类 号：R338.2[医药卫生—人体生理学] R322.8[医药卫生—基础医学] R563.8