Simultaneous detection of both nitric oxide and reactive oxygen species in guinea pig vestibular sensory cells.
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.
Takumida
Masaya
M
Department of Otolaryngology, Hiroshima University Faculty of Medicine, Hiroshima, Japan. masati@hiroshima-u.ac.jp
Anniko
Matti
M
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
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