Figure 2.

Cisplatin increases the cochlear migration of inflammatory cells. Male Wistar rats administrated with cisplatin (11mg/kg, i.p.) and the rats (n=6 in each group) were sacrificed 24, 48, and 72 h later. Mid-modiolar sections of cochleae were prepared to examine the migration of immune cells based on the expression of CD68 (mainly macrophage) and CD45 (neutrophils and other white cells). (A) CD68 labeling was observed in the stria vascularis, spiral ligament and spiral ganglion which was enhanced by cisplatin treatment for 24 h and was progressively increased over a 72h period, especially in the stria vascularis and spiral limbus. (B) CD45 labeling showed time-dependent increases starting at 24 h and becoming more intense by 72 h. Labeling was observed in the stria vascularis and spiral ligament, spiral limbus and in regions surrounding the spiral ganglion and auditory nerve. Labeling in the stria vascularis was substantially elevated by 48 and 72 h, especially in the marginal and deeper cell layers. Darker stained areas in the stria vascularis in (A, B) appear to be associated with perivascular macrophages. Red arrows indicate regions showing increases in CD68 and CD45 immunolabeling. Scale bars – black = 50 µm, red = 20 µm.