IGF1 and stroke disorder: Dosing at 1 mg/kg resulted in a significant decrease in infarct volume when treatment started either 3 hrs or 1-day post-stroke but not when dosing started 5-days post-stroke (vehicle, 1.45 ± 0.09 mm3 versus 1 mg/kg PEG-IGF-I (3 hrs), 0.56 ± 0.04 mm3, P < 0.0001; 1-day, 1.21 ± 0.03 mm3, P = 0.0429; 5-day, 1.27 ± 0.12 mm3, P = 0.2726: n = 5 per group; Fig. 2B).