Effects of insulin-like growth factor-1 on the nerve function and expression of basic fibroblast growth factor after cerebral ischemic reperfusion in rats

Objective To observe dynamically the influence of Insulin-like growth factor-1(IGF-1) on the nerve function and expression of bFGF protein and Basic fibroblast growth factor(bFGF) mRNA after cerebral ischemic reperfusion in rats. Methods Seventy-two SD rats were randomly divided into sham-operated group, cerebral ischemia group, and IGF-1 treated group. The rat model of middle cerebral artery occlusion (MCAO) and reperfusion was performed. The evaluation of etiology was performed with mNSS at 12 h, 24 h, 3 d, 7 d after ischemia-reperfusion, expression of bFGF protein was determined with immunohistochemical technique and expression of bFGF mRNA was determined with RT-PCR. Results The ratings of mNSS in IGF-1 treated group((8.67±1.21), (7.50±1.52), (4.33±1.03), (3.67±1.37)) were lower than those in ischemia group((11.0±1.26), (9.83±1.33), (7.83±1.17), (7.17±1.72) at 12 h, 24 h, 3 d or7 d after reperfusion(P<0.05). For the IGF-1 treated group, the expression level of bFGF protein was higher than that of the cerebral ischemia group (P<0.05), especially at 12 h after reperfusion (P<0.01). The expression level of bFGF mRNA in the IGF-1 treated group was higher than that of the cerebral ischemia group(P<0.05), especially at 24h after reperfusion(P<0.01). Conclusion IGF-1 treatment has a protective effects on cerebral ischemia injury , which may contribute to its action on regulating expression of bFGF protein and bFGF mRNA. Key words: Ischemia; Insulin-like growth factor-1; Basic fibroblast growth factor