OBJECTIVE: To investigate the effects of basic fibroblast growth factor(bFGF) on neurons following hypoxic-ischemic brain damage(HIBD) in neonatal rats. METHODS: Seven-day-old Wistar rats were randomly assigned into a sham operation group, an HIBD group, and 2 bFGF-treated(10 μg/kg and 17.5 μg/k g) HIBD groups(n=8 for each group). The HIBD model using the carotid ligation were previously established. In the bFGF groups, the rats received bFGF by intrapritoneal injection for 7 days. The rats in the untreated HIBD group were injected with normal saline(NS) intraperitoneally at the same time as the bFGF groups. Micro-morphological features and activities of acetylcholinesterase(AchE) and acid phosphatase(ACP) in the HIBD rats treated with bFGF were compared with those in the untreated HIBD rats. RESULTS: Two weeks after HI, the brain ipsilateral to the carotid ligation was severely injured, having selective neuronal cell death, gliosis in the striatum and cortex of the untreated HIBD group; these findings were reduced in the bFGF-treated groups. AchE activity in the damaged neurons of the striatum and cortex obviously decreased in the HIBD group, but was nevertheless higher in the bFGF-treated groups than in the untreated animals. ACP activity in the injured neurons of the ipsilater al striatum increased markedly, but the increase in ACP activity was less in the bFGF groups than in the untreated HIBD group. There were no significant differences in the outcome between the two bFGF dosages.CONCLUSIONS: bFGF may promote the recovery of enzyme activities and the micro-morphological structure of neurons in the striatum and cortex following HI.