IGF1 and Stroke: Assessment of PEG-IGF-I-treated animals (1 mg/kg) showed a significant increase in GFAP expression compared to vehicle-treated stroke controls when treatment started from all three time points, 3 hrs, 1-day and 5-days post-stroke (P < 0.01, P < 0.05, P < 0.05 respectively; Fig. 4F), with the greatest increases observed when treatment was started 3 hrs post-stroke.