Phosphorylation of ERK MAPK in cortical periarachnoid CSF before FPI (0 mins), as a function of time (min) after FPI, and 4 h after FPI and additional exogenous administration of uPA (10−7 mol/L) in vehicle (FPI), EEIIMD (1 mg/kg i.v.)+ FPI, and U 0126 (1 mg/kg i.v.)+FPI animals, n=6. Data expressed as percentage of control by ELISA determination of phospho-MAPK and total MAPK isoforms and subsequent normalization to total form. (A) Newborn, (B) juvenile. *P<0.05 compared with corresponding 0 time value. +P<0.05 compared with corresponding FPI non-pretreated value. #P<0.05 compared with corresponding 240 mins non-uPA-treated value. &P<0.05 compared with corresponding newborn value.