FGF-2 and S100beta immunoreactivities increase in reactive astrocytes, but not in microglia, in ascending dopamine pathways following a striatal 6-OHDA-induced partial lesion of the nigrostriatal system.
Partial lesions were induced in rat midbrain dopamine ascending pathways by intrastriatal injection of 6-hydroxydopamine (6-OHDA), and after two weeks changes were observed in the immunoreactivities of S100beta, a calcium-binding protein, and basic fibroblast growth factor (FGF-2), which is neurotrophic. Semiquantitative microdensitometric image analysis revealed increased intensities of FGF-2 and S100beta immunostaining in putative glial profiles of the ipsilateral neostriatum, pars compacta (SNc) and reticulata (SNr) of the substantia nigra and ventral tegmental area (VTA). Double immunofluorescence and immunoperoxidase procedures, using antibodies against glial fibrillary acidic protein and OX-42, showed that these increased immunoreactivities were restricted to reactive astrocytes; they were not observed in reactive microglia. These results indicate that reactive astrocytes may exert paracrine trophic actions through S100beta and FGF-2 in the midbrain dopamine ascending pathways after striatal 6-OHDA treatment. Interactions between S100beta and FGF-2 may be relevant to neuronal maintenance and repair following dopamine injury.
Chadi
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Laboratory of Neuroregeneration, Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, Avenida Prof. Lineu Prestes 2415, 05508-900-São Paulo, Brazil. gerchadi@usp.br
Gomide
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D000818:Animals; D000954:Antigens, Surface / Q000378:metabolism; D001253:Astrocytes / Q000378:metabolism*; D002450:Cell Communication / Q000502:physiology; D003714:Denervation; D004195:Disease Models, Animal; D004298:Dopamine / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005911:Gliosis / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D017628:Microglia / Q000378:metabolism; D017072:Neostriatum / Q000378:metabolism* / Q000503:physiopathology; D009414:Nerve Growth Factors / Q000378:metabolism*; D009416:Nerve Regeneration / Q000502:physiology; D009434:Neural Pathways / Q000378:metabolism* / Q000503:physiopathology; D016627:Oxidopamine; D019899:Paracrine Communication / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism*; D013378:Substantia Nigra / Q000378:metabolism* / Q000503:physiopathology; D015854:Up-Regulation / Q000502:physiology; D017557:Ventral Tegmental Area / Q000378:metabolism / Q000503:physiopathology
D000954:Antigens, Surface; D005904:Glial Fibrillary Acidic Protein; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D016222:Fibroblast Growth Factor 2; D016627:Oxidopamine; D004298:Dopamine