Reduction of ischemic brain injury by topical application of insulin-like growth factor-I after transient middle cerebral artery occlusion in rats

In order to examine the effect of insulin-like growth factor-1 (IGF-1) on i schemic brain injury, IGF-1 was applied topically on the surface of reperfu sed rat brain after 60 min of transient middle cerebral artery occlusion (M CAO). In contrast to the cases treated with vehicle, the infarct area was g reatly reduced at 24 h of reperfusion by treatment with IGF-1. Terminal deo xynucleotidyl transferase mediated dUTP-biotin in situ nick labeling (TUNEL ) staining and immunoreactivity for glycogen synthase kinase 3 beta (GSK3 b eta) were also markedly reduced in the brains with IGF-1 treatment. The pre sent results suggest that the treatment with IGF-1 significantly ameliorate s rain injury after transient focal brain ischemia associated with the redu ction of TUNEL and GSK3 beta stainings. (C) 2000 Elsevier Science B.V. All rights reserved.