Involvement of poly(ADP-ribose) synthetase in acoustic trauma of the cochlea.
We investigated effects of poly(ADP-ribose) synthetase (PARS) inhibitors on acoustic trauma. Albino guinea pigs were intravenously given 3-aminobenzamide, nicotinamide or 3-aminobenzoic acid (an inactive analog of 3-aminobenzamide) just prior to exposure to a 2 kHz pure tone of 120 dB sound pressure level (SPL) for 10 minutes. The threshold of the compound action potential (CAP) and the amplitude of distortion-product otoacoustic emissions (DPOAEs) were measured before and 4 hours after the acoustic overexposure. Statistically significant decreases in the CAP threshold shifts and significant increases in the DPOAE amplitudes were observed 4 hours after the acoustic overexposure in the animals treated with 3-aminobenzamide or nicotinamide, whereas 3-aminobenzoic acid did not exert any protective effect. These results strongly suggest that excessive activation of PARS is involved in generation of the acoustic trauma.
Tabuchi
Keiji
K
Department of Otolaryngology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba 305-8575, Japan. ktabuchi@md.tsukuba.ac.jp
Hoshino
Tomohumi
T
Murashita
Hidekazu
H
Oikawa
Keiko
K
Uemaetomari
Isao
I
Nishimura
Bungo
B
Tobita
Tadamichi
T
Hara
Akira
A
D000161:Acoustic Stimulation / Q000009:adverse effects; D000200:Action Potentials / Q000502:physiology; D062365:Aminobenzoates / Q000008:administration & dosage / Q000378:metabolism; D000818:Animals; D001549:Benzamides / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism; D003051:Cochlea / Q000473:pathology*; D004789:Enzyme Activation; D006168:Guinea Pigs; D006317:Hearing Loss, Noise-Induced / Q000378:metabolism*; D018696:Neuroprotective Agents / Q000737:chemistry / Q000378:metabolism; D009536:Niacinamide / Q000008:administration & dosage / Q000378:metabolism; D017084:Otoacoustic Emissions, Spontaneous; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D062368:meta-Aminobenzoates
D062365:Aminobenzoates; D001549:Benzamides; D018696:Neuroprotective Agents; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D062368:meta-Aminobenzoates; D009536:Niacinamide; C025160:3-aminobenzamide; D011065:Poly(ADP-ribose) Polymerases; C044855:3-aminobenzoic acid