title: Effects of Pluronic F-68 on Tetrahymena cells: protection against chemical and physical stress and prolongation of survival under toxic conditions.
abstract: The effects of the non-ionic surfactant Pluronic F-68 (0.01% w/v) on Tetrahymena cells have been studied. A marked protection against chemical and physical stress was observed. The chemical stress effects were studied in cells suspended in buffer (starvation) or in buffers with added ingredients from a chemically defined medium (Ca2+, Mg2+, Na+, K+, trace metal ions). The physical stress was due to mechanical stress or hyperthermia. The data show that Pluronic: (a) prolongs the survival of low concentration cell suspensions during starvation; (b) prevents the cell death caused by low concentrations of Ca2+ (70 microM); (c) prolongs the survival of cells exposed to higher ion concentrations (10 mM Ca2+, or Na+ or K+); (d) postpones the death caused by trace metal ions like Zn2+, Fe3+ and, Cu2+; (e) protects cells from the death caused by shearing forces; and (f) prolongs the survival of cells exposed to hyperthermia (43 degrees C). The cellular survival is increased at reduced temperatures (e.g. 4 degrees C instead of 36 degrees C) and at increased cellular concentrations (e.g. 100 cells ml(-1) instead of 25 or 10 cells ml(-1)). There is no effect of pre-incubation with Pluronic. The protective effect of Pluronic towards Tetrahymena is observed for concentrations in the range from 0.001 to 0.1% w/v.
authors.affiliation: IMBG, Department of Biochemistry B, The Panum Institute, University of Copenhagen, Denmark. hellung@imbg.ku.dk
authors.forename: P
authors.initials: P
authors.lastname: Hellung-Larsen
authors.forename: F
authors.initials: F
authors.lastname: Assaad
authors.forename: S
authors.initials: S
authors.lastname: Pankratova
authors.forename: B L
authors.initials: BL
authors.lastname: Saietz
authors.forename: L T
authors.initials: LT
authors.lastname: Skovgaard
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D020442:Poloxamer / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology; D013217:Starvation; D013312:Stress, Physiological; D013501:Surface-Active Agents / Q000494:pharmacology*; D016808:Tetrahymena thermophila / Q000187:drug effects* / Q000502:physiology*
chemical_list: D013501:Surface-Active Agents; D020442:Poloxamer; D012964:Sodium; D011188:Potassium; D002118:Calcium