Cocaine treatment was performed as described (Eipper-Mains et al., 2011). Animals were given saline (10 ml/kg/day) or cocaine (10 or 20 mg/kg/day) intraperitoneally for 7 days and locomotor activity was monitored daily using a 15”×15” Plexiglas chamber (PAS Open Field System, San Diego Instruments); after the 7th injection, locomotor activity was three-fold higher in mice receiving cocaine than in mice receiving saline (Figure S1) (Kiraly et al., 2010; Eipper-Mains et al., 2012). Administering 10 mg/kg cocaine on the first and last days produces more reliable locomotor sensitization (locomotor ambulations on day 7 divided by locomotor ambulations on day 1), as originally demonstrated in rats (Pierce et al., 1996), and was used in later experimental sets in this work. Animals were sacrificed by decapitation 24 hours after the final injection with the exception of mice in the withdrawal groups, which were kept in the home cage for 8 or 28 days after the final cocaine dose prior to tissue harvest; elevated locomotor responding was maintained for the 28 day withdrawal period (Figure S1). Quantitative polymerase chain reaction (qPCR) validation was performed
