Localization of gliosis in the corpus striatum of mice following cortical lesions

Localized lesions of the medial and lateral frontal cortex were used to study gliosis, neurofilament content and changes in synaptic density in the mouse striatum. Relationships between the sites of cortical lesions and the localization of changes in different regions of the striatum were examined after 3 and 12 weeks. Independent of the location of frontal cortex lesions, glial fibrillary acidic protein (GFAP) immunoreactivity was increased throughout the entire striatum after 3 weeks. Twelve weeks after lesioning, increases in GFAP were confined to the dorsomedial (DM) striatum following medial cortical lesions, and to the dorsolateral (DL) striatum following lateral cortical lesions, suggesting persistent gliosis only in areas of striatal deafferentation. It appears, therefore, that the mechanisms which induce gliosis after short and long time periods are different.