BFGF AND FGFR-3 IMMUNOREACTIVITY IN THE RAT-BRAIN FOLLOWING SYSTEMIC KAINIC ACID ADMINISTRATION AT CONVULSANT DOSES - LOCALIZATION OF BFGF AND FGFR-3 IN REACTIVE ASTROCYTES, AND FGFR-3 IN REACTIVE MICROGLIA

Strong bFGF immunoreactivity was observed in reactive astrocytes, as s hown by double-labeling immunohistochemistry of bFGF and GFAP, from da ys 7 up to 30 (last time point examined) following kainic acid (KA) in jection at convulsant doses in the adult rat. bFCF was not found in OX -42-positive reactive microglia. A few reactive glia co-localized FGFR -3 and GFAP, whereas the majority of cells expressing FGFR-3 were OX-4 2-immunoreactive. This was further supported by the observation that o nly approximate to 10% of reactive glia co-localized bFGF and FGFR-3. These results show that reactive astrocytes are a major source of bFGF during the subacute stages of tissue damage following KA injection an d that reactive astrocytes and, most particularly, reactive microglia are putative through FGFR-3. (C) 1997 Elsevier Science B.V.