title: Localized activation of m-calpain in migrating human umbilical vein endothelial cells stimulated by shear stress.
abstract: Using a parallel-plate flow-chamber and confocal laser scanning microscopy (CLSM), we studied the mode of cytoskeletal reorganization in migrating HUVECs stimulated by shear stress. Activation of m-calpain associated with a change in the spatial distribution of cytoplasmic ionized Ca2+ concentration ([Ca2+](i)) was studied. Shear stress (10 dyne/cm(2)) caused migration and decrease in the F-actin content of HUVECs. Migrating individual HUVECs showed the lamellipodium formed in the direction of cell migration, in which [Ca2+](i) elevated to 148 +/- 12 nM in a localized fashion. We found the appearance of activated m-calpain in the local area of the migrating HUVECs, which was associated with a decrease in the amounts of pp125FAK and ezrin. The localized rise in [Ca2+](i) might be closely related to morphological change to regulate the direction of cell migration induced by shear stress through localized activation of m-calpain.
authors.affiliation: Department of Surgery II, Osaka University Medical School, 2-2 Yamada-oka, Suita, Osaka 565, Japan. ariyoshi@surg2.med.osaka-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Ariyoshi
authors.forename: N
authors.initials: N
authors.lastname: Yoshikawa
authors.forename: Y
authors.initials: Y
authors.lastname: Aono
authors.forename: Y
authors.initials: Y
authors.lastname: Tsuji
authors.forename: A
authors.initials: A
authors.lastname: Ueda
authors.forename: M
authors.initials: M
authors.lastname: Tokunaga
authors.forename: M
authors.initials: M
authors.lastname: Sakon
authors.forename: M
authors.initials: M
authors.lastname: Monden
mesh_terms: D000814:Aniline Compounds; D002154:Calpain / Q000378:metabolism*; D002465:Cell Movement; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D004789:Enzyme Activation; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D006801:Humans; D008856:Microscopy, Fluorescence; D010750:Phosphoproteins / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology / Q000201:enzymology*; D014966:Xanthenes; D000099149:Ezrin
chemical_list: D000814:Aniline Compounds; D002154:Calpain; D003598:Cytoskeletal Proteins; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D010750:Phosphoproteins; D011505:Protein-Tyrosine Kinases; D014966:Xanthenes; D000099149:Ezrin; C059715:Fluo-3; C496050:PTK2 protein, human