title: Simultaneous detection of both nitric oxide and reactive oxygen species in guinea pig vestibular sensory cells.
abstract: Gentamicin-induced production of reactive oxygen species (ROS) and of nitric oxide (NO) in the vestibular end organs of the guinea pig was investigated by applying two new fluorescence indicators, 4,5-diaminofluorescein diacetate for direct detection of NO and dihydrotetramethylrosamine for ROS. The vestibular sensory cells produced both NO and ROS after exposure to gentamicin. A nonspecific inhibitor of NO synthase, L-NAME, inhibited the production of NO but did not appear to affect the production of ROS following exposure to gentamicin. In contrast, a radical scavenger, D-methionine, or the neurotrophin BDNF suppressed the production of ROS, in turn stimulating NO production. These findings could indicate that both NO and ROS play an important role in aminoglycoside ototoxicity.
authors.affiliation: Department of Otolaryngology, Hiroshima University Faculty of Medicine, Hiroshima, Japan. masati@hiroshima-u.ac.jp
authors.forename: Masaya
authors.initials: M
authors.lastname: Takumida
authors.forename: Matti
authors.initials: M
authors.lastname: Anniko
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019793:Fluorescein / Q000493:pharmacokinetics; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D005839:Gentamicins / Q000494:pharmacology; D006168:Guinea Pigs; D007202:Indicators and Reagents / Q000493:pharmacokinetics; D008715:Methionine / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000032:analysis* / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D017382:Reactive Oxygen Species / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000378:metabolism; D012235:Rhodamines / Q000493:pharmacokinetics; D013136:Spiral Ganglion / Q000737:chemistry* / Q000187:drug effects; D014722:Vestibule, Labyrinth / Q000737:chemistry* / Q000187:drug effects
chemical_list: C414689:4,5-diaminofluorescein diacetate; D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D005456:Fluorescent Dyes; D005839:Gentamicins; D007202:Indicators and Reagents; D017382:Reactive Oxygen Species; D012235:Rhodamines; C068447:dihydrotetramethylrosamine; D009569:Nitric Oxide; D008715:Methionine; D019001:Nitric Oxide Synthase; D019793:Fluorescein; D019331:NG-Nitroarginine Methyl Ester