Characterization of the ethanol-deprivation effect in substrains of C57BL/6 mice

Abstract

Ethanol craving plays a major role in relapse drinking behavior. Relapse and ethanol craving are an important focus for the treatment of alcoholism. The ethanol deprivation effect (EDE) is a widely used animal model of alcohol craving. While the EDE is widely studied in rats, the molecular mechanisms underlying EDE are not clearly understood. The C57BL/6 inbred mouse strain is widely used for behavioral and molecular analyses of ethanol drinking but studies on the EDE have not been reported in this strain. In the present study, we characterized a simple behavioral protocol that rapidly and reliably induced EDE in C57BL/6 mice. Briefly, singlehoused adult male C57BL/6NCrl and C57BL/6J mice were presented at the beginning of dark phase with two-bottle choice drinking containing either 10 % w/v ethanol or tap water for 18-hrs/ day, as well as food ad libitum. Following ethanol drinking for 4 days or 14-days, mice were deprived of ethanol for a period of 4 days. To study EDE, mice were reinstated with two-bottles containing either ethanol (10 % w/v) or water. Mice were exposed to single or multiple ethanol deprivation cycles. Ethanol consumption (g/kg/18-hrs) and percent ethanol preference (% preference/18-hrs) was recorded for individual mice. C57BL/6NCrl mice consumed moderate amounts (4.78 ± 0.63 g/kg) of ethanol but showed robust EDE after ethanol drinking episodes (4 days or 14 days) as evidenced by increased ethanol consumption and ethanol preference following re-instatement of ethanol. While repeated ethanol deprivation in C57BL/6NCrl mice transiently increased ethanol consumption and ethanol preference, the magnitude of these behaviors was reduced as compared to the first deprivation cycle. In contrast, the C57BL/6J substrain consumed substantially higher levels (9.65 ± 0.90 g/kg) of ethanol but did not show a clear EDE after single or multiple ethanol deprivation cycles. In conclusion, we established a simple and reliable behavioral model to study EDE in C57BL/6NCrl mice. A reliable behavioral model to study EDE in inbred C57BL/6NCrl mice could greatly facilitate further studies on molecular mechanisms of ethanol craving behavior.

Environmental Enrichment Blunts Ethanol Consumption after Restraint Stress in C57BL/6 Mice

“…In one such model, two bottles are presented to the animals: one containing tap water and another containing an alcohol solution [4]. Previous studies have shown that alcohol consumption in the two-bottle choice paradigm can be further increased after periods of ethanol deprivation [5, 6, 7, 8], which may mimic some aspects of repeated withdrawals, persistent craving and relapse in humans [9]. This phenomenon is called alcohol deprivation effect (ADE).…”

Transient CNS responses to repeated binge ethanol treatment

“…In rats, however, EtOH withdrawal seizures are typically not observed unless stimulated (but see Clemmesen and Hemmingsen, 1984; Cooper et al, 1979; Devaud et al, 2012; audiogenic triggers Ebel et al, 1979; Gonzalez et al, 1989; McCown and Breese, 1990; e.g., with chemoconvulsants Pinel and Van Oot, 1975; electroconvulsants Pinel and Van Oot, 1978; Ruwe et al, 1986; Shen et al, 2012; Ulrichsen et al., 1992). Repeated deprivations from EtOH, even in the absence of overt withdrawal signs (Heyser et al, 1997), are associated with temporary increases in drinking as quantified using both simple consummatory measures and operant procedures (Backstrom et al, 2004; in mice: Becker and Lopez, 2004; Bell et al, 2004; Colombo et al, 2003; Cowen et al, 2003; Cox et al, 2013; Dayas et al, 2004; Fullgrabe et al, 2007; Funk et al, 2004; Heyser et al, 1997; in rats: Holter et al, 2000; Khisti et al, 2006; Lundqvist et al, 1995; Melendez et al, 2006; Oster et al, 2006; Sanchis-Segura et al, 2006; Serra et al, 2003; Spanagel and Holter, 1999; Sparta et al, 2009; but see Stephens et al, 2001; Zghoul et al, 2007). …”

Agouti C57BL/6N embryonic stem cells for mouse genetic resources

“…This analysis confirmed their C57BL/6N origin. Although the J and N substrains are very closely related — only 102 of 139,561 SNPs genotyped in these lines are discordant — several phenotypic differences have been noted12,13.…”