ABSTRACT
<p><b>OBJECTIVE</b>To explore the neuroprotective effect of vasoactive intestinal peptide (VIP) in rat ischemic brain injury.</p><p><b>METHODS</b>VIP was administered via intracerebroventricular injection in SD rats prior to focal cerebral ischemia by intraluminal occlusion of the middle cerebral artery. The infarct volume was assessed with TTC staining, and immunohistochemistry was performed to analyze the S100beta expression in the cerebral tissue, with the serum concentrations of S100beta detected by double-antibody sandwich enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>After VIP injection, the relative infarct volume in the rats with cerebral ischemia was significantly reduced by 32.3% as compared with the volume in the control group on day 1 (P<0.05), and the number of S100beta-positive cells was significantly decreased in the cerebral tissue (P<0.05). The injection also resulted in significantly decreased serum S100beta concentrations in the rats (P<0.05).</p><p><b>CONCLUSION</b>VIP injection can reduce the infarct volume in rats with focal cerebral ischemia, suggesting the neuroprotective effect of VIP in brain ischemia possibly by reducing S100beta overexpression.</p>