title: Tri-n-butyltin-induced blockade of store-operated calcium influx in rat thymocytes.
abstract: Tri-n-butyltin (TBT), one of environmental pollutants, disturbs intracellular Ca(2+) homeostasis by increasing intracellular Ca(2+) concentration ([Ca(2+)]i). Effect of TBT on oscillatory change in [Ca(2+)]i (Ca(2+) oscillation) of rat thymocytes was examined using a laser microscope with fluo-3-AM in order to further elucidate the TBT toxicity related to intracellular Ca(2+). The Ca(2+) oscillation was completely attenuated by 300nM TBT. Since store-operated Ca(2+) channels are involved in the generation of Ca(2+) oscillation, the action of TBT on an increase in [Ca(2+)]i by Ca(2+) influx through store-operated Ca(2+) channels was examined. The increase in [Ca(2+)]i by the store-operated Ca(2+) influx was not affected by 3nM TBT. However, TBT at 10nM or more significantly reduced the increase in [Ca(2+)]i. It is likely that TBT attenuates the Ca(2+) oscillation by reducing the Ca(2+) influx through store-operated Ca(2+) channels.
authors.affiliation: Laboratory of Cellular Signaling, Faculty of Integrated Arts and Sciences, The University of Tokushima, Tokushima 770-8502, Japan.
authors.forename: Aimi
authors.initials: A
authors.lastname: Kanada
authors.forename: Jun-Ya
authors.initials: JY
authors.lastname: Yamaguchi
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Tomohiro M
authors.initials: TM
authors.lastname: Oyama
authors.forename: Masaya
authors.initials: M
authors.lastname: Satoh
authors.forename: Norihiro
authors.initials: N
authors.lastname: Katayama
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Chikutei
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Okano
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Oyama