EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR MESSENGER-RNA STIMULATED BY BASIC FIBROBLAST GROWTH-FACTOR AND PLATELET-DERIVED GROWTH-FACTOR IN RAT HIPPOCAMPAL CELL-LINE

Brain-derived neurotrophic factor (BDNF) promotes neuronal cell surviv al and differentiation in the central nervous system. BDNF mRNA is exp ressed at high levels in hippocampus and BDNF serves as a trophic fact or in primary cultures of rat hippocampus. A hippocampal stem cell lin e HiB5, which is immortalized by the temperature sensitive SV 40 T ant igen, undergoes neuronal differentiation at non-permissive temperature s. During the differentiation process, platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) facilitate cell survi val and differentiation in HiB5 cells as well as in primary cultures o f rat embryonic hippocampal cells. This report demonstrates that HiB5 cells express a functionally active PDGF beta receptor and that PDGF a nd bFGF stimulate the expression of BDNF within 2 h. These results pro pose that BDNF is a candidate mediator of trophic effects of PDGF and bFGF in the hippocampal stem cell line HiB5.