Layers of interstitial fluid flow along a“slit-shaped”vascular adventitia  

作　　者：Hongyi LI You LYU Xiaoliang CHEN Bei LI Qi HUA Fusui JI Yajun YIN Hua LI 

机构地区：[1]Cardiology Department,Xuanwu Hospital,Capital Medical University,Beijing 100053,China [2]Cardiology Department,Beijing Hospital,National Center of Gerontology,Institute of Geriatric Medicine,Chinese Academy of Medical Sciences,Beijing 100730,China [3]Radiology Department,China-Japan Friendship Hospital,Beijing 100029,China [4]Department of Engineering Mechanics,Tsinghua University,Beijing 100084,China [5]Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2021年第8期647-663,共17页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：supported by the National Natural Science Foundation of China(Nos.82050004 and 81141118);the Beijing Hospital Clinical Research 121 Project(No.121-2016002);the National Basic Research Program of China(No.2015CB554507);Ms.Siu TUEN,Lucy Chan LAU,Mr.Waichun TIN,and Weiwu HU for their financial support。

摘　　要：Interstitial fluid(ISF)flow through vascular adventitia has been discovered recently.However,its kinetic pattern was unclear.We used histological and topographical identification to observe ISF flow along venous vessels in rabbits.By magnetic resonance imaging(MRI)in live subjects,the inherent pathways of ISF flow from the ankle dermis through the legs,abdomen,and thorax were enhanced by paramagnetic contrast.By fluorescence stereomicroscopy and layer-by-layer dissection after the rabbits were sacrificed,the perivascular and adventitial connective tissues(PACTs)along the saphenous veins and inferior vena cava were found to be stained by sodium fluorescein from the ankle dermis,which coincided with the findings by MRI.The direction of ISF transport in a venous PACT pathway was the same as that of venous blood flow.By confocal microscopy and histological analysis,the stained PACT pathways were verified to be the fibrous connective tissues,consisting of longitudinally assembled fibers.Real-time observations by fluorescence stereomicroscopy revealed at least two types of spaces for ISF flow:one along adventitial fibers and another one between the vascular adventitia and its covering fascia.Using nanoparticles and surfactants,a PACT pathway was found to be accessible by a nanoparticle of<100 nm and contained two parts:a transport channel and an absorptive part.The calculated velocity of continuous ISF flow along fibers of the PACT pathway was 3.6-15.6 mm/s.These data revealed that a PACT pathway was a"slit-shaped"porous biomaterial,comprising a longitudinal transport channel and an absorptive part for imbibition.The use of surfactants suggested that interfacial tension might play an essential role in layers of continuous ISF flow along vascular vessels.A hypothetical"gel pump"is proposed based on interfacial tension and interactions to regulate ISF flow.These experimental findings may inspire future studies to explore the physiological and pathophysiological functions of vascular ISF or interfacial fluid flow among in

关 键 词：Vascular adventitia Interstitial fluid Connective tissue Interfacial zone 

分 类 号：R318[医药卫生—生物医学工程]