Development of distortion product otoacoustic emissions in C57BL/6J mice.
Distortion product otoacoustic emissions (DPOAEs) have been used to examine the development of hearing in the rat and gerbil. However, no reports of DPOAE measurement from the onset of hearing in mice are available. Commercially-available components were assembled and adapted to provide a suitable probe microphone and sound delivery system for measuring DPOAE in developing C57BL/6J mice. Furthermore, DPOAE data were compared with the findings of the auditory brainstem response (ABR). DPOAEs were obtained at 8 kHz from 11 days after birth, 20 kHz from 12 days, and 30 kHz from 13 days. Adult-like patterns of DPOAE were obtained 21 days at 8 and 20 kHz, and 28 days at 30 kHz. On the other hand, the ABR thresholds at 12 to 36 kHz appeared between 11 and 12 days and were saturated at 14 days. Based on these data, the onset of measureable DPOAEs in the mouse were earlier than in the rat and gerbil. The maturation of DPOAE in the mouse begins at a lower frequency in the high frequency range. In addition, the ABR threshold reached maturation earlier than DPOAE.
Department of Otorhinolaryngology, Juntendo University School of Medicine, Tokyo, Japan.
Yuya
Y
Narui
Akira
A
Minekawa
Takashi
T
Iizuka
Masayuki
M
Furukawa
Takeshi
T
Kusunoki
Takuji
T
Koike
Katsuhisa
K
Ikeda
D000704:Analysis of Variance; D000818:Animals; D001933:Brain Stem / Q000254:growth & development* / Q000502:physiology*; D004424:Ear Canal / Q000254:growth & development* / Q000502:physiology*; D004581:Electronics / Q000295:instrumentation; D016057:Evoked Potentials, Auditory, Brain Stem; D051379:Mice; D008810:Mice, Inbred C57BL; D017084:Otoacoustic Emissions, Spontaneous; D011312:Pressure; D013016:Sound; D013045:Species Specificity; D013997:Time Factors