title: Measuring the vascular diameter of brain surface and parenchymal arteries in awake mouse.
abstract: The present study reports a semiautomatic image analysis method for measuring the spatiotemporal dynamics of the vessel dilation that was fluorescently imaged with either confocal or two-photon microscope. With this method, arterial dilation induced by whisker stimulation was compared between cortical surface and parenchymal tissue in the vibrissae area of somatosensory cortex in awake Tie2-GFP mice in which the vascular endothelium had genetically expressed green fluorescent protein. We observed that a mean arterial diameter during a pre-stimulus baseline state was 39 ± 7, 19 ± 1, 16 ± 4, 17 ± 4, and 14 ± 3 μm at depths of 0, 100, 200, 300, and 400 μm, respectively. The stimulation-evoked dilation induced by mechanical whisker deflection (10 Hz for 5 s) was 3.4 ± 0.8, 1.8 ± 0.8, 1.8 ± 0.9, 1.6 ± 0.9, and 1.5 ± 0.6 μm at each depth, respectively. Consequently, no significant differences were observed for the vessel dilation rate between the cortical surface and parenchymal arteries: 8.8 %, 9.9 %, 10.9 %, 9.2 %, and 10.3 % relative to their baseline diameters, respectively. These preliminary results demonstrate that the present method is useful to further investigate the quantitative relationships between the spatiotemporally varying arterial tone and the associated blood flow changes in the parenchymal microcirculation to reveal the regulatory mechanism of the cerebral blood flow.
authors.affiliation: Department of Integrated Design Engineering, Keio University, Yokohama, Japan.|Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Sekiguchi
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan. masamoto@mce.uec.ac.jp.|Center for Frontier Science and Engineering, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo, 182-8585, Japan. masamoto@mce.uec.ac.jp.
authors.forename: Kazuto
authors.initials: K
authors.lastname: Masamoto
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takuwa
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawaguchi
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Iwao
authors.initials: I
authors.lastname: Kanno
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.affiliation: Department of Neurology, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tomita
authors.affiliation: Department of Neurology, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Itoh
authors.affiliation: Department of Neurology, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Suzuki
authors.affiliation: Department of Integrated Design Engineering, Keio University, Yokohama, Japan.|Department of System Design Engineering, Keio University, Yokohama, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Sudo
authors.affiliation: Department of Integrated Design Engineering, Keio University, Yokohama, Japan.|Department of System Design Engineering, Keio University, Yokohama, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanishita
mesh_terms: D000818:Animals; D001158:Arteries / Q000033:anatomy & histology* / Q000502:physiology; D001921:Brain / Q000098:blood supply*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology; D051379:Mice; D010812:Physical Stimulation / Q000379:methods; D013003:Somatosensory Cortex / Q000098:blood supply; D014664:Vasodilation / Q000502:physiology; D014738:Vibrissae / Q000502:physiology