Expression and functions of fibroblast growth factor 2 (FGF-2) in hippocampal formation.

Among the 23 members of the fibroblast growth factor (FGF) family, FGF-2 is the most abundant one in the central nervous system. Its impact on neural cells has been profoundly investigated by in vitro and in vivo studies as well as by gene knockout analyses during the past 2 decades. Key functions of FGF-2 in the nervous system include roles in neurogenesis, promotion of axonal growth, differentiation in development, and maintenance and plasticity in adulthood. From a clinical perspective, its prominent role for the maintenance of lesioned neurons (e.g., ischemia and following transection of fiber tracts) is of particular relevance. In the unlesioned brain, FGF-2 is involved in synaptic plasticity and processes attributed to learning and memory. The focus of this review is on the expression of FGF-2 and its receptors in the hippocampal formation and the physiological and pathophysiological roles of FGF-2 in this region during development and adulthood.