title: Computational models of hair cell bundle mechanics: III. 3-D utricular bundles.
abstract: Six utricular hair bundles from a red-eared turtle are modeled using 3-D finite element analysis. The mechanical model includes shear deformable stereocilia, realignment of all forces during force load increments, and tip and lateral link inter-stereocilia connections. Results show that there are two distinct bundle types that can be separated by mechanical bundle stiffness. The more compliant group has fewer total stereocilia and short stereocilia relative to kinocilium height; these cells are located in the medial and lateral extrastriola. The stiff group are located in the striola. They have more stereocilia and long stereocilia relative to kinocilia heights. Tip link tensions show parallel behavior in peripheral columns of the bundle and serial behavior in central columns when the tip link modulus is near or above that of collagen (1x10(9) N/m(2)). This analysis shows that lumped parameter models of single stereocilia columns can show some aspects of bundle mechanics; however, a distributed, 3-D model is needed to explore overall bundle behavior.
authors.affiliation: Department of Engineering Science and Mechanics and School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University, Mail Code 0219, Blacksburg, VA 24061, USA.
authors.forename: Joe
authors.initials: J
authors.lastname: Silber
authors.forename: John
authors.initials: J
authors.lastname: Cotton
authors.forename: Jong-Hoon
authors.initials: JH
authors.lastname: Nam
authors.forename: Ellengene H
authors.initials: EH
authors.lastname: Peterson
authors.forename: Wally
authors.initials: W
authors.lastname: Grant
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D006198:Hair Cells, Auditory / Q000502:physiology* / Q000648:ultrastructure; D021621:Imaging, Three-Dimensional; D008432:Mathematical Computing; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D012444:Saccule and Utricle / Q000502:physiology* / Q000648:ultrastructure; D014426:Turtles