LOCALIZATION OF GLIOSIS IN THE CORPUS STRIATUM OF MICE FOLLOWING CORTICAL-LESIONS

Localized lesions of the medial and lateral frontal cortex were used t o study gliosis, neurofilament content and changes in synaptic density in the mouse striatum. Relationships between the sites of cortical le sions and the localization of changes in different regions of the stri atum were examined after 3 and 12 weeks. Independent of the location o f frontal cortex lesions, glial fibrillary acidic protein (GFAP) immun oreactivity 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 t he dorsolateral (DL) striatum following lateral cortical lesions, sugg esting persistent gliosis only in areas of striatal deafferentation. I t appears, therefore, that the mechanisms which induce gliosis after s hort and long time periods are different.