title: Mechanical manipulation of bone and cartilage cells with 'optical tweezers'.
abstract: The single beam optical gradient trap (optical tweezers) uses a single beam of laser light to non-invasively manipulate microscopic particles. Optical tweezers exerting a force of approximately 7 pN were applied to single bone and cartilage derived cells in culture and changes in intracellular calcium levels were observed using Fluo-3 labelling. Human derived osteoblasts responded to optical tweezers with an immediate increase in [Ca2+]i that was inhibited by the addition of a calcium channel blocker nifedipine. Force applied to different regions of cells resulted in a variable response. [Ca2+]i elevation in response to load was lower in rat femur derived osteoblasts, and not apparent in primary chondrocytes and the osteocytic cell line (MLO Y4).
authors.affiliation: Centre for Science and Technology in Medicine, School of Postgraduate Medicine, Keele University, North Staffs Hospital, Thornburrow Drive, Stoke on Trent, UK.
authors.forename: L M
authors.initials: LM
authors.lastname: Walker
authors.forename: A
authors.initials: A
authors.lastname: Holm
authors.forename: L
authors.initials: L
authors.lastname: Cooling
authors.forename: L
authors.initials: L
authors.lastname: Maxwell
authors.forename: A
authors.initials: A
authors.lastname: Oberg
authors.forename: T
authors.initials: T
authors.lastname: Sundqvist
authors.forename: A J
authors.initials: AJ
authors.lastname: El Haj
mesh_terms: D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000378:metabolism; D002356:Cartilage / Q000166:cytology* / Q000378:metabolism; D002478:Cells, Cultured; D006801:Humans; D007834:Lasers; D008853:Microscopy / Q000379:methods; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism
chemical_list: D020746:Calcium Channels, L-Type; D002118:Calcium