Strain differences in response to escapable and inescapable novel environments and their ability to predict amphetamine-induced locomotor activity

Abstract

These data suggest that responses to different novelty situations are strain-dependent.

Inbred Lewis and Fischer 344 rat strains differ not only in novelty- and amphetamine-induced behaviors, but also in dopamine transporter activity in vivo

“…The lack of consistency among previous studies reporting differential locomotor effects of acute psychostimulants in LEW and F344 rats (George et al 1991;Camp et al 1994;Kosten et al 1994;Brodkin et al 1998;Stöhr et al 1998;Haile et al 2001;Fernandez et al 2003;Miserendino et al 2003) may be attributable, at least in part, to this procedural factor. However, in at least one study, differences in AMPHinduced locomotion between LEW and F344 rats were not associated with differences in corticosterone levels or fecal boli responses (Miserendino et al 2003). Nonetheless, we thought it important to attempt to minimize injection-related stress in our behavioral experiments by using an indwelling venous catheter, which required very little handling or restraint of the rat during the short (< 5 s) infusion procedure.…”

“…The influence of environmental novelty on strain differences in several of the AMPH responses is not surprising given results from outbred rat strains suggesting that familiarity with the open-field environment significantly influences cocaineinduced behavior (Kiyatikin 1992;Carey et al, 2005). The lack of consistency among previous studies reporting differential locomotor effects of acute psychostimulants in LEW and F344 rats (George et al 1991;Camp et al 1994;Kosten et al 1994;Brodkin et al 1998;Stöhr et al 1998;Haile et al 2001;Fernandez et al 2003;Miserendino et al 2003) may be attributable, at least in part, to this procedural factor. However, in at least one study, differences in AMPHinduced locomotion between LEW and F344 rats were not associated with differences in corticosterone levels or fecal boli responses (Miserendino et al 2003).…”

“…Earlier reports on response to novelty in these rat strains have been somewhat inconsistent (Camp et al 1994;Rex et al 1996;Simar et al 1996;Stöhr et al 1998;Haile et al 2001;Miserendino et al 2003). Methodological differences, as well as established strain differences to stress, likely contributed to these conflicting results.…”

“…For example, compared to LEW rats, F344 rats are reported to have greater AMPH-induced locomotion at doses between 1 and 2 mg/kg (George et al, 1991;Miserendino et al, 2003; but see Camp et al, 1994, for methamphetamine). LEW rats, in contrast, tend to exhibit greater behavioral sensitization after repeated cocaine or methamphetamine treatment (Camp et al 1994;Kosten et al 1994;Haile et al 2001) and enhanced conditioned place preference for cocaine, nicotine and morphine (Guitart et al 1992;Kosten et al 1994;Horan et al 1997).…”

Behavioral genetic contributions to the study of addiction-related amphetamine effects

“…Some studies report large strain differences, which under controlled environmental conditions, could be due to genetic differences. Rat strains have also been found to be differentially sensitive to amphetamines (Camp et al, 1994;Miserendino et al, 2003;Segal et al, 1975), and one study found that the strain distribution patterns for sensitivity to the locomotor stimulant effects of cocaine and d-amphetamine were not identical (George et al, 1991). However, even for two of the most commonly used inbred mouse strains (or sometimes their sublines), C57BL/6 and DBA/2, the strain sensitivity order for amphetamine locomotor response has not been consistent (Anisman et al, 1975;Cabib et al, 2000;Orsini et al, 2004;Phillips et al, 1994;Remington and Anisman, 1976;Wenger, 1989;Zocchi et al, 1998).…”