title: Mechanically induced intracellular calcium waves in osteoblasts demonstrate calcium fingerprints in bone cell mechanotransduction.
abstract: An early response to mechanical stimulation of bone cells in vitro is an increase in intracellular calcium concentration ([Ca (2+)](i)). This study analyzed the [Ca (2+)](i) wave area, magnitude, duration, rise time, fall time, and time to onset in individual osteoblasts for two identical bouts of mechanical stimulation separated by a 30-min rest period. The area under the [Ca (2+)](i) wave increased in the second loading bout compared to the first. This suggests that rest periods may potentiate mechanically induced intracellular calcium signals. Furthermore, many of the [Ca (2+)](i) wave parameters were strongly, positively correlated between the two bouts of mechanical stimulation. For example, in individual primary osteoblasts, if a cell had a large [Ca (2+)](i) wave area in the first bout it was likely to have a large [Ca (2+)](i) wave area in the second bout (r (2) = 0.933). These findings support the idea that individual bone cells have "calcium fingerprints" (i.e., a unique [Ca (2+)](i) wave profile that is reproducible for repeated exposure to a given stimulus).
authors.affiliation: Department of Mechanical Engineering-Engineering Mechanics, Michigan Technological University, Houghton, MI 49931, USA.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Godin
authors.forename: Sakiko
authors.initials: S
authors.lastname: Suzuki
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Jacobs
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Donahue
authors.forename: Seth W
authors.initials: SW
authors.lastname: Donahue
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000166:cytology* / Q000378:metabolism*; D002118:Calcium / Q000032:analysis / Q000378:metabolism*; D020013:Calcium Signaling; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism; D016014:Linear Models; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D051379:Mice; D010006:Osteoblasts / Q000378:metabolism*; D051381:Rats
chemical_list: D002118:Calcium