Forty six adult male rats from the 78th generation of selective breeding for alcohol preference (P line) were purchased from the Indiana University Alcohol Research Resource Center. At the onset of the study, all rats were between 239–251 days of age. Rats were housed individually in stainless steel hanging cages that were located in an isolated vivarium with temperature controlled at 21±1°C, and with a 12 hour light/dark cycle with dark onset at 1000 hours. Standard rodent chow (Laboratory Rodent Diet #7001, Harlan Teklad, Madison, WI) and water were available ad libitum. All experimental procedures were in compliance with the NIH Guide for the Care and Use of Laboratory Animals in addition to being approved by the Indiana University Institutional Animal Care and Use Committee.
