In general, the P line has received the most attention when testing compounds for reducing alcohol abuse and dependence (Table 4). The next most commonly tested line is the AA line followed closely by the sP line. As with innate neurobiology, the HAD lines have received the least amount of research regarding compounds to treat alcohol abuse and dependence. In Table 4, 27% (73/266) of the experiments were conducted in female rats, 39% (103/266) of the experiments evaluated the effects of a compound on operant self-administration, and of the home-cage experiments half (84/163) were free-choice continuous access (FCCA) and half (85/163) were free-choice limited access (FCLA). The effects of a compound on (a) acquisition of ethanol intake were examined in 10 studies (4 with P rats and 6 with sP rats), (b) ethanol-seeking were examined in 9 studies (5 with P rats and 4 with AA rats), and (c) relapse to ethanol-drinking behavior were examined in 9 studies (all of these conducted with P rats). In general, the vast majority of studies were conducted on the maintenance of ethanol drinking
