Early changes to the extracellular space in the hippocampus under simulated microgravity conditions  

作　　者：Yajuan Gao Hongbin Han Jichen Du Qingyuan He Yanxing Jia Junhao Yan Hui Dai Bin Cui Jing Yang Xunbin Wei Liu Yang Rui Wang Ren Long Qiushi Ren Xing Yang Jiabin Lu 

机构地区：[1]Department of Radiology,Peking University Third Hospital,Beijing 100191,China [2]Institute of Medical Technology,Peking University Health Science Center,Beijing 100191,China [3]Beijing Key Laboratory of Magnetic Resonance Imaging Technology,Beijing 100191,China [4]Department of Neurology,Aerospace Center Hospital,Peking University Aerospace Clinical College,Beijing 100039,China [5]State Key Laboratory of Natural and Biomimetic Drugs,School of Pharmaceutical Sciences,Peking University,Beijing 100191,China [6]Department of Anatomy and Histology,School of Basic Medical Sciences,Peking University,Beijing 100191,China [7]NHC Key Laboratory of Medical Immunology,Department of Immunology,School of Basic Medical Sciences,Peking University,Beijing 100191,China [8]Department of Radiology,Aerospace Center Hospital,Peking University Aerospace Clinical College,Beijing 100039,China

出　　处：《Science China(Life Sciences)》2022年第3期604-617,共14页中国科学（生命科学英文版）

基　　金：supported by the National Science Fund for Distinguished Young Scholars(61625102);the National Natural Science Foundation of China(61971011)。

摘　　要：The smooth transportation of substances through the brain extracellular space(ECS)is crucial to maintaining brain function;however,the way this occurs under simulated microgravity remains unclear.In this study,tracer-based magnetic resonance imaging(MRI)and DECS-mapping techniques were used to image the drainage of brain interstitial fluid(ISF)from the ECS of the hippocampus in a tail-suspended hindlimb-unloading rat model at day 3(HU-3)and 7(HU-7).The results indicated that drainage of the ISF was accelerated in the HU-3 group but slowed markedly in the HU-7 group.The tortuosity of the ECS decreased in the HU-3 group but increased in the HU-7 group,while the volume fraction of the ECS increased in both groups.The diffusion rate within the ECS increased in the HU-3 group and decreased in the HU-7 group.The alterations to ISF drainage and diffusion in the ECS were recoverable in the HU-3 group,but neither parameter was restored in the HU-7 group.Our findings suggest that early changes to the hippocampal ECS and ISF drainage under simulated microgravity can be detected by tracer-based MRI,providing a new perspective for studying microgravity-induced nano-scale structure abnormities and developing neuroprotective approaches involving the brain ECS.

关 键 词：brain extracellular space interstitial fluid interstitial system tracer-based magnetic resonance imaging simulated microgravity hindlimb-unloading 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]