FIGURE 4.

Microglial activation in the LA contributes to chronic moderate noise‐induced anxiety‐like behaviors. (A) Schematic for local minocycline injection in the LA to inactivate microglia, and the timeline for noise exposure, minocycline injection, staining, and behavioral tests. (B) Typical images of Iba‐1 immunofluorescence (left), magnified view of the typical microglia (middle), and 3D reconstruction of microglia in the LA of 28‐day moderate noise‐exposed mice treated with minocycline or saline. (C–E) Summarized data of and total process lengths (C, t(12) = 9.406, p < 0.0001, n = 7 mice/group), the total branch points (D, t(12) = 9.545, p < 0.0001, n = 7 mice/group), and normalized soma size (E, t(12) = 15.57, p < 0.0001, n = 7 mice/group) of Iba‐1⁺ microglia measured by the semi‐automated cell morphometry analysis tool in Imaris software. (F and G) Typical voltage traces (F) and summarized data of spontaneous firing rates in the LA of 28‐day moderate noise‐exposed mice injected with minocycline or saline (G, t(8) = 7.774, p < 0.0001, n = 5 mice/group). (H–I) Summarized data of time spent in the center (H, t(16) = 4.632, p = 0.0003, n = 9 mice/group) and total distance traveled (I, t(16) = 0.7691, p = 0.4530, n = 9 mice/group) in the OFT; time spent in the open arms of the EPM (J, t(16) = 8.039, p < 0.0001, n = 9 mice/group) in 28‐day moderate noise‐exposed mice treated with minocycline or saline. Data are expressed as the means ± s.e.m. ***p < 0.001. NS, not significant. Student's unpaired t‐tests were used for (C–E), (G–J). Details of the statistical analyses are presented in Table S1.