INTRACISTERNAL BASIC FIBROBLAST GROWTH-FACTOR (BFGF) ENHANCES BEHAVIORAL RECOVERY FOLLOWING FOCAL CEREBRAL INFARCTION IN THE RAT

Basic fibroblast growth factor (bFGF) is a potent neurotrophic agent t hat promotes neuronal survival and outgrowth. Previous studies have sh own that bFGF, administered intraventricularly or intravenously before or within hours after ischemia, reduces infarct size and neurological deficits in models of focal cerebral ischemia in rats. In the current study, we tested the hypothesis that bFGF, administered at later time points after ischemia, might improve behavioral recovery without affe cting infarct size. Mature Sprague-Dawley rats received bFGF(I mu g/in jection) or vehicle by biweekly intracisternal injection for 4 weeks, starting at 1 day following permanent proximal middle cerebral artery (MCA) occlusion. Animals were examined every other day using four diff erent behavioral tests to assess sensorimotor and reflex function. At 4 weeks after ischemia, there was no difference in infarct volume betw een bFGF- and vehicle-treated animals. There was, however, an enhancem ent in the rate and degree of behavioral recovery among bFGF-treated a nimals, as measured by all four tests. There were no apparent side eff ects of bFGF treatment, except that bFGF-treated animals tended to rec over body weight more slowly than did vehicle-treated animals followin g stroke. The mechanisms of enhancement of behavioral recovery by bFGF require further study, but may include protection against retrograde neuronal death and/or stimulation of neuronal sprouting.