Phosphorylated c-Jun-terminal kinase (JNK) mitogen activated protein kinase (MAPK) (pg/mL) before (0 time) and 4 h after fluid percussion injury (FPI) in (A) newborn male and female pigs and in (B) juvenile male and female pigs before (sham), after FPI, and after FPI treated with epinephrine (EPI), n = 5. *p < 0.05 compared with corresponding 0 time value, +p < 0.05 compared with corresponding FPI alone value, #p < 0.05 compared with corresponding female value.