Age-related differences in hearing function and cochlear morphology between male and female Fischer 344 rats
In old F344 males, the hearing thresholds were higher, the ABR amplitudes were smaller and DPOAE amplitudes were smaller than those measured in females of the same age. There were no gender differences in the number of surviving outer hair cells and the number of inner hair cell ribbon synapses in aged animals, but stria vascularis was evidently more damaged in F344 males compared with females. The aged F344 males can be used as an animal model of strial presbycusis in humans.
Dr. Francesca Chiumentiu University of Padova, Padova, Itálie
RNDr. Jiří Popelář, CSc.; tel.: 241 062 689; firstname.lastname@example.org
Z. Balogová, J. Popelář, F. Chiumenti, T. Chumak, J. Svobodová Burianová, N. Rybalko, J. Syka. Age-related differences in hearing function and cochlear morphology between male and female Fischer 344 rats. Front. Aging Neurosci. doi: 10.3389/fnagi.2017.00428
Cochlear whole mounts from 27-month-old Fischer 344 rats.
Examples of cochlear whole mounts from 27-month-old rats, showing IHC ribbon synapses (green), in F344 males (A) and females (B), and IHCs and OHCs (red) in F344 males (C) and females (D). Cell nuclei are counterstained with DAPI (blue). E - The average number of surviving OHCs in individual tonotopical regions of the organ of Corti in F344 males and females. F - the average number of IHC ribbon synapses per one IHC localized in individual tonotopical regions of the organ of Corti in F344 males and females.
Cross sections of the old F344 rats. Examples of cochlear cross-sections showing the structure of stria vascularis in young rats (A, B) and in 27-month old female (C) and male (D) rats F344. The surface layer of stria vascularis cells in old males is significantly impaired in contrast to the preserved structure of stria vascularis in old female F344 rats.