Figure 2.

Mean ± SD auditory brainstem response (ABR) thresholds in young and old B6.CAST mice with or without the β2 subunit. ABR thresholds were measured for 2-month-old β2+/+ (6 male and 6 female) and β2-/- (4 male and 8 female) mice and also for 8-month-old wild-type AHL allele with β2+/+ (5 male and 5 female) and β2-/- (8 male and 6 female) mice. Significant differences in 8-month-old mice between β2+/+ and β2-/- mice were found across all five frequencies tested (two-way ANOVA on ranks with Dunn multiple comparisons; p < 0.01).