Research Paper Volume 8, Issue 9 pp 2081—2099

Age-related hearing loss: prevention of threshold declines, cell loss and apoptosis in spiral ganglion neurons


Figure 8. MCR presence in spiral ganglion neurons from young adult (3 mon), and aged (21 mon) control mice and those which were treated aldosterone (ALD) from 17 months up to 21 month. (a) mRNA gene expression of MCRs in young adult, aged mice and aged mice with ALD treatment were all of similar magnitudes. 3 mon: Modiolar samples from young adult mice, 21 mon: Modiolar samples from aged mice. L-Ladder: DNA molecular weight. (b) The MCR protein expression level was determined by densitometry analysis (MetaMorph Image Analysis System) of immunocytochemistry sections; upper panels show representative sections for the MCR antibody staining. The insets in the upper panels represent a typical MCR-DAB stained spiral ganglion neuron. The lower panel presents a bar graph summarizing the relative densities from densitometry measurements: Mean ± SEM for each group. (c) MCR protein expression in spiral ganglion neurons shown by western blots of modiolar tissue samples. The expression level is reported relative to the expression of beta-actin as the loading control. For both measures of protein expression (b and c), the ALD treatments helped rescue the age-related declines in MCR protein expression. Statistical significance: *p< 0.05, **p<0.01, ***p<0.005, ****p<0.001.