EN
The distribution and density of cells enwrapped with perineuronal nets (PNs) were examined in the neocortex after unilateral photothrombotic stroke. After different survival times PNs was visualized using Wisteria fl oribunda aglutinin (WFA) staining in the infarct core, peri-infarct and remote cortical areas. Sham operated rats and contralateral hemisphere to the stroke site from experimental rats served as controls. In the infarct core, 4 h after stroke only few cells enwrapped with PNs could be detected and none of numerous dying cells present showed PNs, as revealed by double staining (WFA and FJ-C). No cells with PNs were found 24 h after stroke. In the peri-infarct area, dramatic loss of PNs-enwrapped cells occurred (96%) as compared with the contralateral site, and such cells were almost absent after 24 h. However, 30 days after stroke, a signifi cant number of cells with PNs reappeared. In remote cortical areas, 4h after stroke a reduction in the number of cells with PNs was observed. After 24 h the loss of PNs-enwrapped cells was profound (63%) in comparison to intact hemisphere. However, 7d after stroke complete restoration of the number of cells enwrapped with PNs took place. The density of cells with PNs was similar to that found in the contralateral site and in sham operated rats. These results showed the wide spreading and transient effect of photothrombosis on PNs in remote cortical areas. Supported by MNiSW Grant N3030300832/0474 and statutory funds.