Effects of withdrawal from chronic escalating-dose binge cocaine on conditioned place preference to cocaine and striatal preproenkephalin mRNA in C57BL/6J mice

► Penk mRNA increased after cocaine CPP following 14 day withdrawal from cocaine. ► Penk mRNA did not change after cocaine CPP following 1 day withdrawal from cocaine. ► Mice did not form cocaine CPP after 1-day withdrawal from 14 day chronic cocaine. ► Mice developed cocaine CPP after 14-days withdrawal from 14-day chronic cocaine.