Deafferentation-Induced Redistribution of MMP-2, but Not of MMP-9, Depends on the Emergence of GAP-43 Positive Axons in the Adult Rat Cochlear Nucleus

Figure 5

Time course of the distribution of MMP-9 and MMP-2 following combination of KA injection completely lesioning VNTB and cochlear ablation (KAcL + CA). (a)–(c) The distribution of MMP-9 showed no differences compared to the pattern following cochlear ablation alone (Figure 1(a)–1(d)). Compared to control animals (a), the cytoplasm of AVCN neurons (arrows in (a)) have lost MMP-9 by POD3 (b) but regained it till POD7 (c). Beaded collars close to the plasma membrane were particularly prominent around POD3 (arrowheads in (b)). (d–f) As in case with cochlear ablation alone (Figures 1(e)–1(h)), the cytoplasm of AVCN neurons partially lost their MMP-2 immunoreactivity by POD3 (e). By POD7, MMP-2 immunoreactivity in cytoplasm of neurons was almost back to control level (d) again (f). Scale bar: 20 μm. Global contrast adjustment was identical for all photographs in this figure.