title: [Ca2+]i independent mitogenesis in cultured human fibroblasts revealed by single cell microfluorimetry.
abstract: A transient rise in intracellular free Ca2+ concentration ([Ca2+]i) has been implicated in mitogenic induction of cell division. Individual human foreskin fibroblasts in confluent cultures examined with the Ca2+ indicator Fura-2 and a fluorescence microscope-imaging system had a basal [Ca2+]i which varied markedly from cell-to-cell. A transient serum-induced rise in [Ca2+]i was demonstrated the magnitude of which was directly correlated with the basal [Ca2+]i level. In contrast to serum-induced increase in [Ca2+]i, exposure to an elevated level of extracellular Ca2+, which is at least equally mitogenic for fibroblasts, did not alter the basal [Ca2+]i of single subconfluent cells or confluent cells. Elevated extracellular Ca2+ does not exert its mitogenicity via a transient rise in [Ca2+]i.
authors.affiliation: USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA.
authors.forename: F C
authors.initials: FC
authors.lastname: Praeger
authors.forename: L
authors.initials: L
authors.lastname: Reinlib
authors.forename: M
authors.initials: M
authors.lastname: Donowitz
authors.forename: B A
authors.initials: BA
authors.lastname: Gilchrest
mesh_terms: D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D002452:Cell Count; D002478:Cells, Cultured; D003592:Cytophotometry; D005110:Extracellular Space / Q000502:physiology; D005312:Fetal Blood / Q000502:physiology; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D016257:Fura-2; D006801:Humans; D007231:Infant, Newborn; D008938:Mitosis
chemical_list: D001572:Benzofurans; D002118:Calcium; D016257:Fura-2