FIGURE 1.

Experimental groups and behavior outcomes timeline. Animals used in the study were male Sprague Dawley pups. Random assignment was made of 80 male pups from 8 dams to either have treatment at postnatal day 6 (P6) of anesthesia and surgery or anesthesia alone with half of the pups in each group from each dam. Sutures were removed at P10 and animals weaned at P21. Random assignment of animals into behavioral outcome measurement was made with equal numbers of surgery and anesthesia and sham anesthesia from each dam; 16 animals were placed in the five choice serial reaction time titration variant (5CTV) group for measurement of attention and distraction, 12 animals were placed into the heroin self-administration (SA) group, and 40 animals were placed into the open field discrimination (OFT)/Tail Suspension Test (TST). Twelve additional animals were not included as no animal was excluded from loss or failure to train and all animals initially entered into the experiment randomly were used for the experiment. As a result a total of 68 animals were studied as only 16 could be studied in the 5CTV and 12 in the self-administration paradigm.