Grant-in-Aid for International Scientific Research.
|Section||Joint Research .|
Biomedical engineering/Biological material science
|Research Institution||Tohoku University|
SATO Masaaki Tohoku Univ.Grad Sch Engng, Prof, 大学院・工学研究科, 教授 (30111371)
GIRARD Peggy ジョージア工科大学, 生物学科, 講師
NEREM Robert ジョージア工科大学, 機械工学科, 教授
大橋 俊朗 東北大学, 工学部, 助手 (30270812)
KATAOKA Noriyuki Tohoku Univ.Grad Sch Engng, Res Associate, 大学院・工学研究科, 助手 (20250681)
MATSUMOTO Takeo Tohoku Univ.Grad Sch Engng, Assoc Prof, 大学院・工学研究科, 助教授 (30209639)
DEWEY Jr. C. マサチューセッツ工科大学, 機械工学科, 教授
HELLUMS J.Da ライズ大学, 化学工学科, 教授
HELLAMS J.Da ライス大学, 化学工学科, 教授
NEREM Robert M Georgia Tech, Sch Mech Engng, Prof
GIRARD Peggy R Georgia Tech, Sch Biology, Assistant Prof
HELLUMS J David Rice Univ, Chemical Engng, Prof
|Project Fiscal Year
1995 – 1997
Completed(Fiscal Year 1997)
|Budget Amount *help
¥11,100,000 (Direct Cost : ¥11,100,000)
Fiscal Year 1997 : ¥3,800,000 (Direct Cost : ¥3,800,000)
Fiscal Year 1996 : ¥3,800,000 (Direct Cost : ¥3,800,000)
Fiscal Year 1995 : ¥3,500,000 (Direct Cost : ¥3,500,000)
|Keywords||vascular endothelial cells / actin filament / shear stress / permeability / atherosclerosis / GFP / 血管内皮細胞 / アクチン線維 / せん断応力 / 物質透過性 / 動脈硬化 / 物質速過性 / 内皮細胞 / アクチンフィラメント / アテローム性動脈硬化|
As this year was the last term of this project, we examined our results obtained for the past two years form global point of view, and decided to develop some new experimental methods to overcome methodological problems in the previous studies.
1. DEVELOPMENT OF A NEW TECHNIQUE TO OBSERVE ACTIN FILAMENTS IN ALIVE CELLS
Immunofluorescence technique which has been utilized widely to observe intracellular actin filaments requires fixation of the cells, and it was vey difficult to observe actin filament dynamics in intact cells. To overcome this problem, we have introduced a combined gene of alpha-actinin, a bridging element of actin filaments and GFP (Green Fluorescent Protein) into vascular endothelial cells. Cells introduced such genes have autofluorescence in their alpha-actinin, and thus their actin filaments. We successfully observed actin filament dynamics in cells under static and shear-exposed conditions.
2. DEVELOPMENT OF A FLOW-LOADING SYSTEM FOR ENDOTHELIAL CELLS ON ARTERIAL INTRALUMINAL SURFACE
There have been a lot of contradictions between results obtained from animal experiments and that based on cultured endothelial cells. To establish a new method compensating shortcomings of both experiments, we have developed a new flow-loading system to impose shear stress on the endothelial surface of an arterial segment, in which a piece of a cut-opened arterial segment is laid flat to expose its intraluminal surface to flow in a parallel plate chamber. We applied 1 Pa of shear stress to rabbit thoracic aortas perpendicularly to their vessel axis, and found that most of the endothelial cells changed their alignment parallel to the direction of flow in 72 hours. We concluded that this system can be widely used for the future studies on the mechanical response of vascular endothelial cells to shear stress.