DIFFERENTIAL PATTERNS OF LAMININ EXPRESSION IN LATERAL AND MEDIAL MIDBRAIN GLIA

AN analysis of the extra cellular matrix (ECM) in regionally heterogen eous midbrain glia has been started. Immunoreactivity to laminin has b een tested in confluent glial cultures from lateral (L) and medial (M) sectors of 14 days mouse embryos (E14) and in neurone-glia cocultures kept for 48 hours after plating of E14 midbrain freshly-dissociated n eurones. Laminin is present in both types of glial cultures, but its d istribution assumes a punctate pattern in glia that is not permissive for neurite growth (M-glia) and a fibrillar configuration in a favoura ble glial substrate (L-glia). Moreover, laminin expression is dramatic ally upregulated in co-cultures although fibrillar and punctate patter ns are maintained.