title: Effects of a time varying strong magnetic field on release of cytosolic free Ca2+ from intracellular stores in cultured bovine adrenal chromaffin cells.
abstract: This study was made to explain the mechanisms for the effects of exposure to a time varying 1.51 T magnetic field on the intracellular Ca(2+) signaling pathway. The exposure inhibited an increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) in bovine chromaffin cells induced by addition of bradykinin (BK) to a Ca(2+) free medium. The exposure did not change BK induced production of inositol 1,4,5-trisphosphate (IP(3)). [Ca(2+)](i) was markedly increased in IP(3) loaded cells, and this increase was inhibited by the magnetic field exposure. A similar increase in [Ca(2+)](i) by other drugs, which stimulated Ca(2+) release from intracellular Ca(2+) stores, was again inhibited by the same exposure. However, transmembrane Ca(2+) fluxes caused in the presence of thapsigargin were not inhibited by the magnetic field exposure in a Ca(2+) containing medium. Inhibition of the BK induced increase in [Ca(2+)](i) by the exposure for 30 min was mostly recovered 1 h after exposure ended. Our results reveal that the magnetic field exposure inhibits Ca(2+) release from intracellular Ca(2+) stores, but that BK bindings to BK receptors of the cell membrane and intracellular inositol IP(3) production are not influenced.
authors.affiliation: Department of Physiology, School of Medicine, The University of Tokushima, Kuramoto-cho, Tokushima 770-8503, Japan.
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Ikehara
authors.forename: Ki Ho
authors.initials: KH
authors.lastname: Park
authors.forename: Hisao
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Keiko
authors.initials: K
authors.lastname: Hosokawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Houchi
authors.forename: Mami
authors.initials: M
authors.lastname: Azuma
authors.forename: Kazuo
authors.initials: K
authors.lastname: Minakuchi
authors.forename: Hideki
authors.initials: H
authors.lastname: Kashimoto
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kitamura
authors.forename: Yohsuke
authors.initials: Y
authors.lastname: Kinouchi
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yoshizaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyamoto
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D001920:Bradykinin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002477:Cells; D019439:Chromaffin Cells / Q000378:metabolism* / Q000528:radiation effects*; D004574:Electromagnetic Fields; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D015544:Inositol 1,4,5-Trisphosphate; D001920:Bradykinin; D002118:Calcium