Paravascular microcirculation facilitates rapid lipid transport and astrocyte signaling in the brain

1] Division of Glia Disease and Therapeutics, Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York 14642 [2] Letten Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway [3] Centre for Molecular Medicine Norway, Nordic EMBL Partnership, University of Oslo, 0318 Oslo, Norway [4].
Scientific Reports (Impact Factor: 5.08). 09/2013; 3:2582. DOI: 10.1038/srep02582
Source: PubMed

ABSTRACT In the brain, a paravascular space exists between vascular cells and astroglial end-foot processes, creating a continuous sheath surrounding blood vessels. Using in vivo two-photon imaging we demonstrate that the paravascular circulation facilitates selective transport of small lipophilic molecules, rapid interstitial fluid movement and widespread glial calcium signaling. Depressurizing the paravascular system leads to unselective lipid diffusion, intracellular lipid accumulation and pathological signaling in astrocytes. As the central nervous system is devoid of lymphatic vessels, the paravascular space may serve as a lymphatic equivalent that represents a separate highway for the transport of lipids and signaling molecules.

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