title: Tri-n-butyltin delays the cell death induced by hydrogen peroxide in rat thymocytes.
abstract: Tri-n-butyltin (TBT), one of environmental pollutants accumulated in mollusks, at nanomolar concentrations decreases cellular content of glutathione (GSH), suggesting that TBT increases cell vulnerability to oxidative stress because GSH has a role in catabolizing hydrogen peroxide (H(2)O(2)). In order to examine this possibility, the effect of tri-n-butyltin chloride (TBTCl) on rat thymocytes suffering from oxidative stress induced by H(2)O(2) was examined using a flow cytometer with four fluorescent probes; ethidium bromide, 2',7'-dichlorofluorescin diacetate, 5-chloromethylfluorescein diacetate and annexin-V-FITC. TBTCl at concentrations ranging from 100 nM to 1 μM attenuated H(2)O(2)-induced decrease in cell viability in a dose-dependent manner. It was unlikely that TBTCl reduced H(2)O(2)-induced oxidative stress because TBTCl failed to affect H(2)O(2)-induced oxidation of intracellular molecule (2',7'-dichlorofluorescin) and H(2)O(2)-induced decrease in cellular content of GSH. Results suggest that TBTCl may inhibit the pathway of cell death induced by H(2)O(2) or that TBTCl may induce a protective substance against the oxidative stress produced by H(2)O(2).
authors.affiliation: Laboratory of Cellular Signaling, Faculty of Integrated Arts and Sciences, The University of Tokushima, Minami-Jyozanjima 1-1, Tokushima 770-8502, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sakai
authors.forename: Y
authors.initials: Y
authors.lastname: Oyama
authors.forename: Y
authors.initials: Y
authors.lastname: Okada
authors.forename: N
authors.initials: N
authors.lastname: Akaike
authors.forename: M
authors.initials: M
authors.lastname: Nakata
authors.forename: L
authors.initials: L
authors.lastname: Chikahisa